Java 如何在android中填充一个在点击按钮时动态生成的微调器
我正在搜索如何在android中点击按钮动态添加/删除布局,并找到了 我使用上述教程中的代码设计了一个页面,每次点击按钮都会生成一个布局。此布局包含一个Java 如何在android中填充一个在点击按钮时动态生成的微调器,java,android,dynamic,nullpointerexception,spinner,Java,Android,Dynamic,Nullpointerexception,Spinner,我正在搜索如何在android中点击按钮动态添加/删除布局,并找到了 我使用上述教程中的代码设计了一个页面,每次点击按钮都会生成一个布局。此布局包含一个微调器,编辑文本和按钮 我的代码在单击按钮时成功添加/删除布局 public class TestActivity extends Activity { Button btnDisplay; ImageButton btnAdd; LinearLayout container; @Override pr
微调器
,编辑文本
和按钮
我的代码在单击按钮时成功添加/删除布局
public class TestActivity extends Activity {
Button btnDisplay;
ImageButton btnAdd;
LinearLayout container;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
container = findViewById(R.id.linearLayoutForm);
btnAdd = (ImageButton) findViewById(R.id.btnAdd);
btnDisplay = (Button) findViewById(R.id.btnDisplay);
btnAdd.setOnClickListener(addListener);
//TODO: btnDisplay
}
/*
* We define our OnClickListener that will act when we click on the btn.
*/
View.OnClickListener addListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
final LinearLayout newView = (LinearLayout) getLayoutInflater().inflate(R.layout.rowdetail, null);
newView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
ImageButton btnRemove = (ImageButton) newView.findViewById(R.id.btnRemove);
btnRemove.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
container.removeView(newView);
}
});
container.addView(newView);
//Now we load your data into your spinner
Spinner s = newView.findViewById(R.id.spinner1);
try {
loadSpinnerData(s);
} catch (IOException e) {
//TODO: catch exception
e.printStackTrace();
}
}
};
/*
* This function is supposed to load the data into the given spinner.
* It would be better to load the data an other way, i.e.: using ASyncTask
*/
private void loadSpinnerData(Spinner s) throws IOException {
// database handler
DBHelper db = new DBHelper(getApplicationContext());
// Spinner Drop down elements
List<String> products = db.getAllProducts();
// Creating adapter for spinner
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, products);
// Drop down layout style - list view with radio button
dataAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
s.setAdapter(dataAdapter);
}
}
因此,我的第一个问题是,所有生成的微调器都是空的,即它们在创建后没有填充数据库中的数据,第二个问题是,我如何从动态创建的微调器/EditText中获取所选/输入的数据,因为我不知道它们的id。
DBHelper
类与我的其他应用程序配合良好,因此我没有将其发布在这里
这是MyLayoutOperation
类:-
public class MyLayoutOperation extends Activity {
static Spinner s;
public static void display(final Activity activity, Button btn)
{
btn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
LinearLayout scrollViewlinerLayout = (LinearLayout) activity.findViewById(R.id.linearLayoutForm);
java.util.ArrayList<String> msg = new ArrayList<String>();
for (int i = 0; i < scrollViewlinerLayout.getChildCount(); i++)
{
LinearLayout innerLayout = (LinearLayout) scrollViewlinerLayout.getChildAt(i);
s = (Spinner) innerLayout.findViewById(R.id.spinner1);
EditText edit = (EditText) innerLayout.findViewById(R.id.editDescricao);
//msg.add(products.getSelectedItem().toString());
msg.add(edit.getText().toString());
}
Toast t = Toast.makeText(activity.getApplicationContext(), msg.toString(), Toast.LENGTH_SHORT);
t.show();
}
});
}
public static void add(final Activity activity, ImageButton btn)
{
final LinearLayout linearLayoutForm = (LinearLayout) activity.findViewById(R.id.linearLayoutForm);;
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
final LinearLayout newView = (LinearLayout)activity.getLayoutInflater().inflate(R.layout.rowdetail, null);
newView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
ImageButton btnRemove = (ImageButton) newView.findViewById(R.id.btnRemove);
btnRemove.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
linearLayoutForm.removeView(newView);
}
});
linearLayoutForm.addView(newView);
}
});
}
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.rowdetail);
s = (Spinner) findViewById(R.id.spinner1);
// Loading spinner data from database
try {
loadSpinnerData();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void loadSpinnerData() throws IOException {
// database handler
DBHelper db = new DBHelper(getApplicationContext());
// Spinner Drop down elements
List<String> products = db.getAllProducts();
// Creating adapter for spinner
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, products);
// Drop down layout style - list view with radio button
dataAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
s.setAdapter(dataAdapter);
}
}
07-22 08:23:27.090: E/AndroidRuntime(1834): FATAL EXCEPTION: main
07-22 08:23:27.090: E/AndroidRuntime(1834): Process: com.example.teste1, PID: 1834
07-22 08:23:27.090: E/AndroidRuntime(1834): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.teste1/com.example.teste1.MainActivity}: java.lang.NullPointerException
07-22 08:23:27.090: E/AndroidRuntime(1834): Caused by: java.lang.NullPointerException
07-22 08:23:27.090: E/AndroidRuntime(1834): at com.example.teste1.MyLayoutOperation.add(MyLayoutOperation.java:73)
07-22 08:23:27.090: E/AndroidRuntime(1834): at com.example.teste1.MainActivity.onCreate(MainActivity.java:22)
07-22 08:23:27.090: E/AndroidRuntime(1834): at android.app.Activity.performCreate(Activity.java:5231)
public class MainActivity extends Activity {
Button btnDisplay;
ImageButton btnAdd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnAdd = (ImageButton) findViewById(R.id.btnAdd);
btnDisplay = (Button) findViewById(R.id.btnDisplay);
MyLayoutOperation.add(this, btnAdd);
MyLayoutOperation.display(this, btnDisplay);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/rowdetail"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<Spinner
android:id="@+id/spinner1"
android:layout_width="94dp"
android:layout_height="45dp" />
<EditText
android:id="@+id/editDescricao"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="0.01"
android:ems="10"
android:inputType="text" />
<ImageButton
android:id="@+id/btnRemove"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/btnRemove"
android:src="@android:drawable/ic_delete" />
</LinearLayout>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/layoutTeste"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context=".MainActivity" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<TextView
android:id="@+id/textView1"
android:layout_width="95dp"
android:layout_height="fill_parent"
android:layout_alignBottom="@+id/btnAdd"
android:layout_alignParentLeft="true"
android:layout_toLeftOf="@+id/btnAdd"
android:gravity="center_vertical|center_horizontal"
android:text="@string/titleTecnologies"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ImageButton
android:id="@+id/btnAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:contentDescription="@string/btnAdd"
android:src="@android:drawable/ic_input_add" />
</RelativeLayout>
<ScrollView
android:id="@+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="275dp" >
<LinearLayout
android:id="@+id/linearLayoutForm"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</ScrollView>
<Button
android:id="@+id/btnDisplay"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/btnDisplay" />
</LinearLayout>
MyLayoutOperation
的第73行:-btn.setOnClickListener(新视图.OnClickListener(){
MainActivity
的第22行:-MyLayoutOperation.add(此,btnAdd);
MainActivity.java
:-
public class MyLayoutOperation extends Activity {
static Spinner s;
public static void display(final Activity activity, Button btn)
{
btn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
LinearLayout scrollViewlinerLayout = (LinearLayout) activity.findViewById(R.id.linearLayoutForm);
java.util.ArrayList<String> msg = new ArrayList<String>();
for (int i = 0; i < scrollViewlinerLayout.getChildCount(); i++)
{
LinearLayout innerLayout = (LinearLayout) scrollViewlinerLayout.getChildAt(i);
s = (Spinner) innerLayout.findViewById(R.id.spinner1);
EditText edit = (EditText) innerLayout.findViewById(R.id.editDescricao);
//msg.add(products.getSelectedItem().toString());
msg.add(edit.getText().toString());
}
Toast t = Toast.makeText(activity.getApplicationContext(), msg.toString(), Toast.LENGTH_SHORT);
t.show();
}
});
}
public static void add(final Activity activity, ImageButton btn)
{
final LinearLayout linearLayoutForm = (LinearLayout) activity.findViewById(R.id.linearLayoutForm);;
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
final LinearLayout newView = (LinearLayout)activity.getLayoutInflater().inflate(R.layout.rowdetail, null);
newView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
ImageButton btnRemove = (ImageButton) newView.findViewById(R.id.btnRemove);
btnRemove.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
linearLayoutForm.removeView(newView);
}
});
linearLayoutForm.addView(newView);
}
});
}
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.rowdetail);
s = (Spinner) findViewById(R.id.spinner1);
// Loading spinner data from database
try {
loadSpinnerData();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void loadSpinnerData() throws IOException {
// database handler
DBHelper db = new DBHelper(getApplicationContext());
// Spinner Drop down elements
List<String> products = db.getAllProducts();
// Creating adapter for spinner
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, products);
// Drop down layout style - list view with radio button
dataAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
s.setAdapter(dataAdapter);
}
}
07-22 08:23:27.090: E/AndroidRuntime(1834): FATAL EXCEPTION: main
07-22 08:23:27.090: E/AndroidRuntime(1834): Process: com.example.teste1, PID: 1834
07-22 08:23:27.090: E/AndroidRuntime(1834): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.teste1/com.example.teste1.MainActivity}: java.lang.NullPointerException
07-22 08:23:27.090: E/AndroidRuntime(1834): Caused by: java.lang.NullPointerException
07-22 08:23:27.090: E/AndroidRuntime(1834): at com.example.teste1.MyLayoutOperation.add(MyLayoutOperation.java:73)
07-22 08:23:27.090: E/AndroidRuntime(1834): at com.example.teste1.MainActivity.onCreate(MainActivity.java:22)
07-22 08:23:27.090: E/AndroidRuntime(1834): at android.app.Activity.performCreate(Activity.java:5231)
public class MainActivity extends Activity {
Button btnDisplay;
ImageButton btnAdd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnAdd = (ImageButton) findViewById(R.id.btnAdd);
btnDisplay = (Button) findViewById(R.id.btnDisplay);
MyLayoutOperation.add(this, btnAdd);
MyLayoutOperation.display(this, btnDisplay);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/rowdetail"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<Spinner
android:id="@+id/spinner1"
android:layout_width="94dp"
android:layout_height="45dp" />
<EditText
android:id="@+id/editDescricao"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="0.01"
android:ems="10"
android:inputType="text" />
<ImageButton
android:id="@+id/btnRemove"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/btnRemove"
android:src="@android:drawable/ic_delete" />
</LinearLayout>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/layoutTeste"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context=".MainActivity" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<TextView
android:id="@+id/textView1"
android:layout_width="95dp"
android:layout_height="fill_parent"
android:layout_alignBottom="@+id/btnAdd"
android:layout_alignParentLeft="true"
android:layout_toLeftOf="@+id/btnAdd"
android:gravity="center_vertical|center_horizontal"
android:text="@string/titleTecnologies"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ImageButton
android:id="@+id/btnAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:contentDescription="@string/btnAdd"
android:src="@android:drawable/ic_input_add" />
</RelativeLayout>
<ScrollView
android:id="@+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="275dp" >
<LinearLayout
android:id="@+id/linearLayoutForm"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</ScrollView>
<Button
android:id="@+id/btnDisplay"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/btnDisplay" />
</LinearLayout>
rowdeail.xml
:-
public class MyLayoutOperation extends Activity {
static Spinner s;
public static void display(final Activity activity, Button btn)
{
btn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
LinearLayout scrollViewlinerLayout = (LinearLayout) activity.findViewById(R.id.linearLayoutForm);
java.util.ArrayList<String> msg = new ArrayList<String>();
for (int i = 0; i < scrollViewlinerLayout.getChildCount(); i++)
{
LinearLayout innerLayout = (LinearLayout) scrollViewlinerLayout.getChildAt(i);
s = (Spinner) innerLayout.findViewById(R.id.spinner1);
EditText edit = (EditText) innerLayout.findViewById(R.id.editDescricao);
//msg.add(products.getSelectedItem().toString());
msg.add(edit.getText().toString());
}
Toast t = Toast.makeText(activity.getApplicationContext(), msg.toString(), Toast.LENGTH_SHORT);
t.show();
}
});
}
public static void add(final Activity activity, ImageButton btn)
{
final LinearLayout linearLayoutForm = (LinearLayout) activity.findViewById(R.id.linearLayoutForm);;
btn.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
final LinearLayout newView = (LinearLayout)activity.getLayoutInflater().inflate(R.layout.rowdetail, null);
newView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
ImageButton btnRemove = (ImageButton) newView.findViewById(R.id.btnRemove);
btnRemove.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
linearLayoutForm.removeView(newView);
}
});
linearLayoutForm.addView(newView);
}
});
}
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.rowdetail);
s = (Spinner) findViewById(R.id.spinner1);
// Loading spinner data from database
try {
loadSpinnerData();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
private void loadSpinnerData() throws IOException {
// database handler
DBHelper db = new DBHelper(getApplicationContext());
// Spinner Drop down elements
List<String> products = db.getAllProducts();
// Creating adapter for spinner
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, products);
// Drop down layout style - list view with radio button
dataAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
s.setAdapter(dataAdapter);
}
}
07-22 08:23:27.090: E/AndroidRuntime(1834): FATAL EXCEPTION: main
07-22 08:23:27.090: E/AndroidRuntime(1834): Process: com.example.teste1, PID: 1834
07-22 08:23:27.090: E/AndroidRuntime(1834): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.teste1/com.example.teste1.MainActivity}: java.lang.NullPointerException
07-22 08:23:27.090: E/AndroidRuntime(1834): Caused by: java.lang.NullPointerException
07-22 08:23:27.090: E/AndroidRuntime(1834): at com.example.teste1.MyLayoutOperation.add(MyLayoutOperation.java:73)
07-22 08:23:27.090: E/AndroidRuntime(1834): at com.example.teste1.MainActivity.onCreate(MainActivity.java:22)
07-22 08:23:27.090: E/AndroidRuntime(1834): at android.app.Activity.performCreate(Activity.java:5231)
public class MainActivity extends Activity {
Button btnDisplay;
ImageButton btnAdd;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnAdd = (ImageButton) findViewById(R.id.btnAdd);
btnDisplay = (Button) findViewById(R.id.btnDisplay);
MyLayoutOperation.add(this, btnAdd);
MyLayoutOperation.display(this, btnDisplay);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/rowdetail"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<Spinner
android:id="@+id/spinner1"
android:layout_width="94dp"
android:layout_height="45dp" />
<EditText
android:id="@+id/editDescricao"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="0.01"
android:ems="10"
android:inputType="text" />
<ImageButton
android:id="@+id/btnRemove"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:contentDescription="@string/btnRemove"
android:src="@android:drawable/ic_delete" />
</LinearLayout>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/layoutTeste"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context=".MainActivity" >
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<TextView
android:id="@+id/textView1"
android:layout_width="95dp"
android:layout_height="fill_parent"
android:layout_alignBottom="@+id/btnAdd"
android:layout_alignParentLeft="true"
android:layout_toLeftOf="@+id/btnAdd"
android:gravity="center_vertical|center_horizontal"
android:text="@string/titleTecnologies"
android:textAppearance="?android:attr/textAppearanceLarge" />
<ImageButton
android:id="@+id/btnAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:contentDescription="@string/btnAdd"
android:src="@android:drawable/ic_input_add" />
</RelativeLayout>
<ScrollView
android:id="@+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="275dp" >
<LinearLayout
android:id="@+id/linearLayoutForm"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</ScrollView>
<Button
android:id="@+id/btnDisplay"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/btnDisplay" />
</LinearLayout>
请帮助。编辑:
你不需要额外的活动。你只需要一个活动,它将显示你的布局,并在你点击按钮时更新它
public class TestActivity extends Activity {
Button btnDisplay;
ImageButton btnAdd;
LinearLayout container;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
container = findViewById(R.id.linearLayoutForm);
btnAdd = (ImageButton) findViewById(R.id.btnAdd);
btnDisplay = (Button) findViewById(R.id.btnDisplay);
btnAdd.setOnClickListener(addListener);
//TODO: btnDisplay
}
/*
* We define our OnClickListener that will act when we click on the btn.
*/
View.OnClickListener addListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
final LinearLayout newView = (LinearLayout) getLayoutInflater().inflate(R.layout.rowdetail, null);
newView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
ImageButton btnRemove = (ImageButton) newView.findViewById(R.id.btnRemove);
btnRemove.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
container.removeView(newView);
}
});
container.addView(newView);
//Now we load your data into your spinner
Spinner s = newView.findViewById(R.id.spinner1);
try {
loadSpinnerData(s);
} catch (IOException e) {
//TODO: catch exception
e.printStackTrace();
}
}
};
/*
* This function is supposed to load the data into the given spinner.
* It would be better to load the data an other way, i.e.: using ASyncTask
*/
private void loadSpinnerData(Spinner s) throws IOException {
// database handler
DBHelper db = new DBHelper(getApplicationContext());
// Spinner Drop down elements
List<String> products = db.getAllProducts();
// Creating adapter for spinner
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, products);
// Drop down layout style - list view with radio button
dataAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
s.setAdapter(dataAdapter);
}
}
公共类测试活动扩展活动{
按钮显示;
图像按钮btnAdd;
线性布局集装箱;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
容器=findViewById(R.id.linearLayoutForm);
btnAdd=(ImageButton)findViewById(R.id.btnAdd);
btnDisplay=(按钮)findViewById(R.id.btnDisplay);
btnAdd.setOnClickListener(addListener);
//待办事项:btnDisplay
}
/*
*我们定义了当我们点击btn时将起作用的OnClickListener。
*/
View.OnClickListener addListener=新视图。OnClickListener(){
@凌驾
公共void onClick(视图v){
最终LinearLayout newView=(LinearLayout)GetLayoutFlater().充气(R.layout.rowdetail,null);
newView.setLayoutParams(新的LayoutParams(ViewGroup.LayoutParams.WRAP_内容,ViewGroup.LayoutParams.WRAP_内容));
ImageButton btnRemove=(ImageButton)newView.findViewById(R.id.btnRemove);
btnRemove.setOnClickListener(新视图.OnClickListener(){
@凌驾
公共void onClick(视图v){
container.removeView(newView);
}
});
container.addView(newView);
//现在,我们将数据加载到微调器中
微调器s=newView.findViewById(R.id.spinner1);
试一试{
加载喷丝头数据;
}捕获(IOE异常){
//TODO:捕获异常
e、 printStackTrace();
}
}
};
/*
*此函数用于将数据加载到给定的微调器中。
*最好以另一种方式加载数据,即使用ASyncTask
*/
私有void loadSpinnerData(微调器s)引发IOException{
//数据库处理程序
DBHelper db=newdbhelper(getApplicationContext());
//微调器下拉元素
List products=db.getAllProducts();
//为微调器创建适配器
ArrayAdapter dataAdapter=新的ArrayAdapter(此,
android.R.layout.simple_微调器(项目、产品);
//下拉式布局样式-带单选按钮的列表视图
数据适配器
.setDropDownViewResource(android.R.layout.simple\u微调器\u下拉菜单\u项);
//将数据适配器连接到微调器
s、 setAdapter(数据适配器);
}
}
我还没有测试过这段代码,所以你可能需要调整它,使它符合你的需要,但我认为主要的想法是存在的。
“活动”的“创建”会使布局膨胀。您可以在其中设置按钮,并保存有关“容器”的信息
单击“添加”按钮,只需将新布局充气,并使用加载SpinnerData;
设置微调器数据,即可将数据库中的数据加载到微调器中
请注意,这不是从数据库获取信息的好方法。这样做可能会阻止UI线程,因为检索大量信息可能会很耗时。最好使用加载程序或异步任务来执行此操作。我可以将您重定向到解释得很好(并且很容易理解)的位置如何有效地管理数据库。编辑:
你不需要额外的活动。你只需要一个活动,它将显示你的布局,并在你点击按钮时更新它
public class TestActivity extends Activity {
Button btnDisplay;
ImageButton btnAdd;
LinearLayout container;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
container = findViewById(R.id.linearLayoutForm);
btnAdd = (ImageButton) findViewById(R.id.btnAdd);
btnDisplay = (Button) findViewById(R.id.btnDisplay);
btnAdd.setOnClickListener(addListener);
//TODO: btnDisplay
}
/*
* We define our OnClickListener that will act when we click on the btn.
*/
View.OnClickListener addListener = new View.OnClickListener() {
@Override
public void onClick(View v) {
final LinearLayout newView = (LinearLayout) getLayoutInflater().inflate(R.layout.rowdetail, null);
newView.setLayoutParams(new LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT));
ImageButton btnRemove = (ImageButton) newView.findViewById(R.id.btnRemove);
btnRemove.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
container.removeView(newView);
}
});
container.addView(newView);
//Now we load your data into your spinner
Spinner s = newView.findViewById(R.id.spinner1);
try {
loadSpinnerData(s);
} catch (IOException e) {
//TODO: catch exception
e.printStackTrace();
}
}
};
/*
* This function is supposed to load the data into the given spinner.
* It would be better to load the data an other way, i.e.: using ASyncTask
*/
private void loadSpinnerData(Spinner s) throws IOException {
// database handler
DBHelper db = new DBHelper(getApplicationContext());
// Spinner Drop down elements
List<String> products = db.getAllProducts();
// Creating adapter for spinner
ArrayAdapter<String> dataAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, products);
// Drop down layout style - list view with radio button
dataAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// attaching data adapter to spinner
s.setAdapter(dataAdapter);
}
}
公共类测试活动扩展活动{
按钮显示;
图像按钮btnAdd;
线性布局集装箱;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
容器=findViewById(R.id.linearLayoutForm);
btnAdd=(ImageButton)findViewById(R.id.btnAdd);
btnDisplay=(按钮)findViewById(R.id.btnDisplay);
btnAdd.setOnClickListener(addListener);
//待办事项:btnDisplay
}
/*
*我们定义了当我们点击btn时将起作用的OnClickListener。
*/
View.OnClickListener addListener=新视图。OnClickListener(){
@凌驾
公共void onClick(视图v){
最终LinearLayout newView=(LinearLayout)GetLayoutFlater().充气(R.layout.rowdetail,null);
newView.setLayoutParams(新的LayoutParams(ViewGroup.LayoutParams.WRAP_内容,ViewGroup.LayoutParams.WRAP_内容));
ImageButton btnRemove=(ImageButton)newView.findViewById(R.id.btnRemov