Java Eclipse,单击按钮上的新活动
我是一个初学者,但我想修改一个旧的项目。 在Preferences活动中,已经有一些按钮,但是我想添加一个新按钮,当单击该按钮时,将打开一个新活动并仅显示一个图像 为此,我在清单中声明了此新活动:Java Eclipse,单击按钮上的新活动,java,android,eclipse,android-layout,import,Java,Android,Eclipse,Android Layout,Import,我是一个初学者,但我想修改一个旧的项目。 在Preferences活动中,已经有一些按钮,但是我想添加一个新按钮,当单击该按钮时,将打开一个新活动并仅显示一个图像 为此,我在清单中声明了此新活动: <activity android:name=".VisualHelpActivity" android:screenOrientation="portrait" android:theme="@style/AppTheme" > </activity> …现在我
<activity
android:name=".VisualHelpActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme" >
</activity>
…现在我要把它连接到“主要”首选项活动中,如下所示:
public class PreferencesActivity extends TranslatableActivity {
public static String url = "https://www.paypal.com/cgi-bin....";
ImageView donate;
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
setContentView(R.layout.activity_preferences);
donate = (ImageView) findViewById(R.id.button_donate);
donate.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
donate(v);
}
});
Spinner s = (Spinner) findViewById(R.id.combo_language);
Lang[] languages = LanguageUtil.Lang.values();
s.setAdapter(new ArrayAdapter<Lang>(this,
android.R.layout.simple_dropdown_item_1line, languages));
s.setSelection(getPosition(languages, LanguageUtil.getLanguage()), true);
}
private int getPosition(Object[] objs, Object item) {
for (int i = 0; i < objs.length; i++) {
if (objs[i] == item)
return i;
}
return -1;
}
public void update(View v) {
Maintenance.downloadDB(this, new onFinishListener() {
@Override
public void onFinish() {
LanguageUtil.loadLanguage(PreferencesActivity.this);
}
});
}
public void copy(View v) {
Maintenance.copyDB(this, new onFinishListener() {
@Override
public void onFinish() {
LanguageUtil.loadLanguage(PreferencesActivity.this);
}
});
}
public void save(View v) {
LanguageUtil.saveLanguage(this,
(Lang) ((Spinner) findViewById(R.id.combo_language))
.getSelectedItem());
LanguageUtil.loadLanguage(this);
setResult(RESULT_OK);
finish();
}
public void donate(View v) {
Intent i = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(i);
}
public void cancel(View v) {
finish();
}
@Override
protected void refreshLanguage() {
((Button) findViewById(R.id.button_update)).setText(LanguageUtil
.getDeviceLabel(LanguageUtil.dev_update));
((TextView) findViewById(R.id.language_label))
.setText(LanguageUtil.getDeviceLabel(LanguageUtil.dev_language));
}
}
唯一的问题是,如果我尝试添加这个新的
public void
,会弹出多个标记错误,如果我尝试在其他地方包含下面的所有内容,我的应用程序将无法工作。那么,有人能帮我找出在何处以及如何包含此代码部分以使其正常工作吗?在您的PreferencesActivity类的oncreate方法中添加如下代码:-
Button button;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
setContentView(R.layout.activity_preferences);
donate = (ImageView) findViewById(R.id.button_donate);
donate.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
donate(v);
}
});
button = (Button) findViewById(R.id.button_visualhelp);
button.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
Intent myIntent = new Intent(PreferencesAtivity.this,
VisualHelpActivity.class);
startActivity(myIntent);
}
});
Spinner s = (Spinner) findViewById(R.id.combo_language);
Lang[] languages = LanguageUtil.Lang.values();
s.setAdapter(new ArrayAdapter<Lang>(this,
android.R.layout.simple_dropdown_item_1line, languages));
s.setSelection(getPosition(languages, LanguageUtil.getLanguage()), true);
}
按钮;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
setContentView(R.layout.activity_首选项);
捐赠=(ImageView)findViewById(R.id.button\u捐赠);
senate.setOnClickListener(新的OnClickListener(){
@凌驾
公共void onClick(视图v){
捐赠(五);
}
});
按钮=(按钮)findViewById(R.id.button\u visualhelp);
setOnClickListener(新的OnClickListener(){
公共void onClick(视图arg0){
Intent myIntent=新的Intent(PreferencesAtivity.this,
VisualHelpActivity.class);
星触觉(myIntent);
}
});
微调器s=(微调器)findViewById(R.id.combo\u语言);
Lang[]languages=LanguageUtil.Lang.values();
s、 setAdapter(新阵列适配器)(此,
android.R.layout.simple_dropdown_item_1line,languages));
s、 setSelection(getPosition(languages,LanguageUtil.getLanguage()),true);
}
您的按钮是在VisualHelpActivity XML文件中还是在PreferencesActivity XML文件中?顺便说一下,这只是一条友好的建议。如果你有一台像样的机器,可以使用Android Studio。如果你有一个英特尔处理器也很好,因为新的仿真器(在最新版本中)非常棒。我的按钮在PreferencesActivity xml上,应该会触发VisualHelpActivity xml,我不能使用Android studio,因为我需要迁移我的项目,我不是很好,这不好,我在androidbegin.com上填写了与我如何理解相关的代码,但似乎我理解得不是很好,因为当我尝试按照您的建议填写时,我得到了一个错误,即Intent myIntent=new Intent(PreferencesAtivity.this,VisualHelpActivity.class)代码>首选项不能解析为类型。我还想问一下public void onClick(View arg0)
,arg0是什么意思?这是一个视图,您按得很糟糕,没有注意代码的正确性,没有检查就复制/粘贴了代码。我错过了PreferencesAtivity中的一个“c”。这是
,因此代码现在编译正确,但按钮仍然无法调用新活动(没有给出错误,只有应用程序崩溃。arg0在查看新活动中起到任何作用吗?正如我提到的,新活动只包括显示图像,上面的代码对于图像“调用”是正确的活动?
public class VisualHelpActivity extends TranslatableActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_visualhelp);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.visual_help, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
protected void refreshLanguage() {
}
}
public class PreferencesActivity extends TranslatableActivity {
public static String url = "https://www.paypal.com/cgi-bin....";
ImageView donate;
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
onBackPressed();
return true;
default:
return super.onOptionsItemSelected(item);
}
}
@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
setContentView(R.layout.activity_preferences);
donate = (ImageView) findViewById(R.id.button_donate);
donate.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
donate(v);
}
});
Spinner s = (Spinner) findViewById(R.id.combo_language);
Lang[] languages = LanguageUtil.Lang.values();
s.setAdapter(new ArrayAdapter<Lang>(this,
android.R.layout.simple_dropdown_item_1line, languages));
s.setSelection(getPosition(languages, LanguageUtil.getLanguage()), true);
}
private int getPosition(Object[] objs, Object item) {
for (int i = 0; i < objs.length; i++) {
if (objs[i] == item)
return i;
}
return -1;
}
public void update(View v) {
Maintenance.downloadDB(this, new onFinishListener() {
@Override
public void onFinish() {
LanguageUtil.loadLanguage(PreferencesActivity.this);
}
});
}
public void copy(View v) {
Maintenance.copyDB(this, new onFinishListener() {
@Override
public void onFinish() {
LanguageUtil.loadLanguage(PreferencesActivity.this);
}
});
}
public void save(View v) {
LanguageUtil.saveLanguage(this,
(Lang) ((Spinner) findViewById(R.id.combo_language))
.getSelectedItem());
LanguageUtil.loadLanguage(this);
setResult(RESULT_OK);
finish();
}
public void donate(View v) {
Intent i = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
startActivity(i);
}
public void cancel(View v) {
finish();
}
@Override
protected void refreshLanguage() {
((Button) findViewById(R.id.button_update)).setText(LanguageUtil
.getDeviceLabel(LanguageUtil.dev_update));
((TextView) findViewById(R.id.language_label))
.setText(LanguageUtil.getDeviceLabel(LanguageUtil.dev_language));
}
}
Button button;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_visualhelp);
button = (Button) findViewById(R.id.button_visualhelp);
button.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
Intent myIntent = new Intent(PreferencesAtivity.this,
VisualHelpActivity.class);
startActivity(myIntent);
}
});
}
Button button;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
setContentView(R.layout.activity_preferences);
donate = (ImageView) findViewById(R.id.button_donate);
donate.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
donate(v);
}
});
button = (Button) findViewById(R.id.button_visualhelp);
button.setOnClickListener(new OnClickListener() {
public void onClick(View arg0) {
Intent myIntent = new Intent(PreferencesAtivity.this,
VisualHelpActivity.class);
startActivity(myIntent);
}
});
Spinner s = (Spinner) findViewById(R.id.combo_language);
Lang[] languages = LanguageUtil.Lang.values();
s.setAdapter(new ArrayAdapter<Lang>(this,
android.R.layout.simple_dropdown_item_1line, languages));
s.setSelection(getPosition(languages, LanguageUtil.getLanguage()), true);
}