无法为Android中的选项卡创建TabListener
我遇到的问题是,我的一位tab听众说无法为Android中的选项卡创建TabListener,android,Android,我遇到的问题是,我的一位tab听众说 Bound mismatch: The type MainActivity is not a valid substitute for the bounded parameter <T extends Fragment> of the type MainActivity.TabListener<T> 绑定不匹配:类型MainActivity不是有效的替代项 对于类型的有界参数 MainActivity.TabListener
Bound mismatch: The type MainActivity is not a valid substitute
for the bounded parameter <T extends Fragment> of the type
MainActivity.TabListener<T>
绑定不匹配:类型MainActivity不是有效的替代项
对于类型的有界参数
MainActivity.TabListener
以下是我的MainActivity.java代码的一部分:
package com.example.currencyconverter;
import android.app.ActionBar;
import android.app.Activity;
import android.app.Fragment;
import android.app.FragmentTransaction;
import android.app.ActionBar.Tab;
import android.app.ActionBar.TabListener;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.View;
import android.view.View.OnClickListener;
public class MainActivity extends Activity implements OnClickListener {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addListenerOnButton();
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
getActionBar().setDisplayShowHomeEnabled(false);
getActionBar().setDisplayShowTitleEnabled(false);
final ActionBar actionBar = getActionBar();
Tab tab = actionBar.newTab()
.setText("Currencies")
.setTabListener(new TabListener<Fragment1>(
this, "Currencies", Fragment1.class));
actionBar.addTab(tab);
Tab tab1 = actionBar.newTab()
.setText("Converter")
.setTabListener(new TabListener<Fragment3>(
this, "Converter", Fragment3.class));
actionBar.addTab(tab1);
Tab tab2 = actionBar.newTab()
.setText("News")
.setTabListener(new TabListener<Fragment2>(
this, "News", Fragment2.class));
actionBar.addTab(tab2);
/*ActionBar actionBar = getActionBar();
actionBar.setSubtitle("Created By Rohit Nandakumar");
actionBar.setTitle("Currency Converter");
// Specify that tabs should be displayed in the action bar.
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
ActionBar.Tab Frag1 = actionBar.newTab().setText("Converter");
ActionBar.Tab Frag2 = actionBar.newTab().setText("Currencies");
ActionBar.Tab Frag3 = actionBar.newTab().setText("News");
Fragment fragment1 = new Fragment1();
Fragment fragment2 = new Fragment2();
Fragment fragment3 = new Fragment3();
Frag1.setTabListener(new MyTabsListener(fragment1));
Frag2.setTabListener(new MyTabsListener(fragment2));
Frag3.setTabListener(new MyTabsListener(fragment3));
actionBar.addTab(Frag1);
actionBar.addTab(Frag2);
actionBar.addTab(Frag3); */
// Create a tab listener that is called when the user changes tabs.
/*ActionBar.TabListener tabListener = new ActionBar.TabListener() {
public void onTabSelected(ActionBar.Tab tab, FragmentTransaction ft) {
String n = tab.getText().toString();
Toast.makeText(getApplicationContext(), "You have selected: " + n, Toast.LENGTH_LONG).show();
if (n.equals("Converter")) {
startActivity(new Intent (MainActivity.this, MainActivity.class));
}
if (n.equals("Currencies")) {
startActivity(new Intent (MainActivity.this, FirstActivity.class));
}
if (n.equals("News")) {
startActivity(new Intent (MainActivity.this, FirstActivity.class));
}
}
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction ft) {
// hide the given tab
}
public void onTabReselected(ActionBar.Tab tab, FragmentTransaction ft) {
// probably ignore this event
}
};
// Add 3 tabs, specifying the tab's text and TabListener
for (int i = 0; i < 3; i++) {
actionBar.addTab(
actionBar.newTab()
.setText(tabTitle[i])
.setTabListener(tabListener));
} */
}
public static class TabListener<T extends Fragment> implements ActionBar.TabListener {
private final Activity mActivity;
private final String mTag;
private final Class<T> mClass;
/** Constructor used each time a new tab is created.
* @param activity The host Activity, used to instantiate the fragment
* @param tag The identifier tag for the fragment
* @param clz The fragment's Class, used to instantiate the fragment
*/
public TabListener(Activity activity, String tag, Class<T> clz) {
mActivity = activity;
mTag = tag;
mClass = clz;
}
/* The following are each of the ActionBar.TabListener callbacks */
public void onTabSelected(Tab tab, FragmentTransaction ft) {
Fragment mFragment = mActivity.getFragmentManager().findFragmentByTag(mTag);
// Check if the fragment is already initialized
if (mFragment == null) {
// If not, instantiate and add it to the activity
mFragment = Fragment.instantiate(mActivity, mClass.getName());
ft.add(android.R.id.content, mFragment, mTag);
} else {
// If it exists, simply attach it in order to show it
ft.attach(mFragment);
}
}
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
Fragment mFragment = mActivity.getFragmentManager().findFragmentByTag(mTag);
if (mFragment != null) {
// Detach the fragment, because another one is being attached
ft.detach(mFragment);
}
}
public void onTabReselected(Tab tab, FragmentTransaction ft) {
// User selected the already selected tab. Usually do nothing.
}
}
class MyTabsListener implements ActionBar.TabListener {
public Fragment fragment;
public MyTabsListener(Fragment fragment) {
this.fragment = fragment;
}
@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
ft.replace(R.id.fragment_container, fragment);
}
@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
ft.remove(fragment);
}
}
package com.example.currencyconverter;
导入android.app.ActionBar;
导入android.app.Activity;
导入android.app.Fragment;
导入android.app.FragmentTransaction;
导入android.app.ActionBar.Tab;
导入android.app.ActionBar.TabListener;
导入android.os.Bundle;
导入android.util.Log;
导入android.view.Menu;
导入android.view.MenuInflater;
导入android.view.view;
导入android.view.view.OnClickListener;
公共类MainActivity扩展活动实现OnClickListener{
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addListenerOnButton();
StrictMode.ThreadPolicy policy=新建StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(策略);
getActionBar().setDisplayShowHomeEnabled(false);
getActionBar().setDisplayShowTitleEnabled(false);
最终ActionBar ActionBar=getActionBar();
Tab=actionBar.newTab()
.setText(“货币”)
.setTabListener(新的TabListener(
这是“货币”,碎片(1.类);
actionBar.addTab(tab);
Tab tab1=actionBar.newTab()
.setText(“转换器”)
.setTabListener(新的TabListener(
这个“转换器”,片段3.class);
actionBar.addTab(表1);
Tab tab2=actionBar.newTab()
.setText(“新闻”)
.setTabListener(新的TabListener(
这是“新闻”,片段2.类);
actionBar.addTab(表2);
/*ActionBar ActionBar=getActionBar();
actionBar.setSubtitle(“由Rohit Nandakumar创建”);
actionBar.setTitle(“货币转换器”);
//指定应在操作栏中显示选项卡。
actionBar.setNavigationMode(actionBar.NAVIGATION\u MODE\u选项卡);
ActionBar.Tab Frag1=ActionBar.newTab().setText(“转换器”);
ActionBar.Tab Frag2=ActionBar.newTab().setText(“货币”);
ActionBar.Tab Frag3=ActionBar.newTab().setText(“新闻”);
Fragment fragment1=新的fragment1();
片段fragment2=新片段2();
Fragment fragment3=新的fragment3();
Fragm1.setTabListener(新MyTabsListener(fragment1));
Fragm2.setTabListener(新MyTabsListener(fragment2));
Fragm3.setTabListener(新MyTabsListener(fragment3));
actionBar.addTab(Frag1);
actionBar.addTab(Frag2);
actionBar.addTab(Frag3)*/
//创建在用户更改选项卡时调用的选项卡侦听器。
/*ActionBar.TabListener TabListener=新建ActionBar.TabListener(){
已选择的公共事务(ActionBar.Tab选项卡,FragmentTransaction ft){
字符串n=tab.getText().toString();
Toast.makeText(getApplicationContext(),“您已选择:”+n,Toast.LENGTH\u LONG.show();
如果(n.等于(“转换器”)){
startActivity(新意图(MainActivity.this、MainActivity.class));
}
如果(n.等于(“货币”)){
startActivity(新意图(MainActivity.this,FirstActivity.class));
}
如果(n.等于(“新闻”)){
startActivity(新意图(MainActivity.this,FirstActivity.class));
}
}
已选择公共无效OnTab(ActionBar.Tab选项卡,FragmentTransaction ft){
//隐藏给定的选项卡
}
已重新选择公共void ontaber(ActionBar.Tab选项卡,FragmentTransaction ft){
//可能忽略此事件
}
};
//添加3个选项卡,指定选项卡的文本和TablListener
对于(int i=0;i<3;i++){
actionBar.addTab(
actionBar.newTab()
.setText(tabTitle[i])
.setTabListener(tabListener));
} */
}
公共静态类TablListener实现ActionBar.TablListener{
私人最终活动能力;
私有最终字符串mTag;
私人期末班;
/**每次创建新选项卡时使用的构造函数。
*@param activity主机活动,用于实例化片段
*@param标记片段的标识符标记
*@param clz片段的类,用于实例化片段
*/
公共TabListener(活动、字符串标记、类clz){
活动性=活动性;
mTag=标签;
mClass=clz;
}
/*下面是ActionBar.TabListener回调的每个部分*/
已选择的公共事务(选项卡,碎片事务ft){
Fragment MFFragment=mActivity.getFragmentManager().findFragmentByTag(mTag);
//检查片段是否已初始化
if(mFragment==null){
//如果不是,则实例化并将其添加到活动中
MFFragment=Fragment.instantiate(mActivity,mClass.getName());
ft.add(android.R.id.content、mFragment、mTag);
}否则{
//如果存在,只需将其附加以显示即可
ft.attach(mFragment);
}
}
已选择公共空页(选项卡,碎片事务ft){
Fragment MFFragment=mActivity.getFragmentManager().findFragmentByTag(mTag);
if(mFragment!=null){
//拆下碎片,因为正在连接另一个碎片
ft.分离(mFragment);
}
}
已重新选择公共无效页签(页签,碎片事务){
//用户选择了已选择的选项卡。通常不执行任何操作。
}
}
类MyTabsListener实现ActionBar.TablListener{
公共碎片;
公共MyTabsListener(片段){
this.fragment=片段;
}
@凌驾
已重新选择公共无效页签(页签,碎片事务){
}
tab = actionBar.newTab()
.setText("Converter")
.setTabListener(new TabListener<MainActivity>(
this, "Converter", MainActivity.class));
actionBar.addTab(tab);
.setTabListener(new TabListener<MainActivity>(
this, "Converter", MainActivity.class));
Tab tab = actionBar.newTab()
.setText("Currencies")
.setTabListener(new TabListener<Fragment1>(
this, "Currencies", Fragment1.class));
TabListener<T extends Fragment>
public static class TabListener implements ActionBar.TabListener {
private Fragment mFragment;
private final Activity mActivity;
private final String mTag;
private final Class mClass;
public TabListener(Activity activity, String tag, Class clz) {
mActivity = activity;
mTag = tag;
mClass = clz;
}
.
.
.
}
import android.app.Fragment;
import android.support.v4.app.Fragment