Question

我有2个活动A和B. A开始B（对于清单中的B，我将标志noHistory设置为true）。在Activity B上有单个Button启动DialogFragment（不添加到backStack）。当对话框启动时，我按下设备上的后退按钮，我看到活动B，但我想看活动A. 暂时我在我的Dialog的onCancel（）中调用getActivity.finish（）解决了这个问题。它有效，但我会对更好的解决方案感到满意。我很感激你的想法。

更新：代码

这是ActivityA：

public class Activity1 extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    Button btn1 = new Button(getApplicationContext());
    btn1.setText("Start Activity2");
    btn1.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,     ViewGroup.LayoutParams.WRAP_CONTENT));
    btn1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent(getApplicationContext(), Activity2.class);
            startActivity(intent);
        }
    });
    setContentView(btn1);
}

}

（这是活动B）

public class Activity2 extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    LinearLayout ll = new LinearLayout(getApplicationContext());
    TextView tv = new TextView(getApplicationContext());
    tv.setText("This is Activity 2");
    Button btn = new Button(getApplicationContext());
    btn.setText("ShowDialog");
    btn.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            FragmentTransaction fragmentTransaction = getFragmentManager().beginTransaction();
            MyDialog dialog = new MyDialog();
            dialog.show(fragmentTransaction, "dialog");
        }
    });
    ll.addView(tv);
    ll.addView(btn);
    setContentView(ll);
}

}

这是Dialog

public class MyDialog extends DialogFragment {

Activity2 activity = null;
@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
    builder.setMessage("SomeMessage")
            .setPositiveButton("Fire", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    // FIRE ZE MISSILES!
                }
            })
            .setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                    // User cancelled the dialog
                }
            });
    // Create the AlertDialog object and return it
    return builder.create();
}

@Override
public void onCancel(DialogInterface dialog) {
    super.onCancel(dialog);
    if(activity != null)
        activity.finish();
//        getActivity().onBackPressed();
}

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);
    if(activity instanceof Activity2) {
        this.activity = (Activity2)activity;
    }
}

}

这是显而易见的

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.example.task_test"
      android:versionCode="1"
      android:versionName="1.0">
<uses-sdk android:minSdkVersion="11"/>
<application android:label="@string/app_name">
    <activity android:name="MyActivity"
              android:label="@string/app_name">
        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>
    </activity>
    <activity android:name=".Activity2"
            android:theme="@android:style/Animation.Dialog"
            android:noHistory="true"/>
    <activity android:name=".Activity3"/>
</application>
</manifest>

使用noHistory启动活动

0 个答案: