问题:

I need to minimize the application when back button is pressed.

I use following code to catch hardware back button click event

help me with the code of minimize on back key pressed

@Override
public boolean onKeyDown(int keyCode, keyEvent event) {
    switch(keyCode) {
    case KeyEvent.KEYCODE_BACK;
    //minimize application
    return true;
    }
    return super.onKeyDown(keyCode, event);
}

回答1:

I think that you need to treat back event as home event. The code below is how I emulate home pressed when User press back button:

 public void minimizeApp() {
    Intent startMain = new Intent(Intent.ACTION_MAIN);
    startMain.addCategory(Intent.CATEGORY_HOME);
    startMain.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
    startActivity(startMain);
}

回答2:

This is a simple code to minimize the application

@Override
public void onBackPressed() {
        this.moveTaskToBack(true);
}

回答3:

try this code, this will minimize Activity.

public boolean onKeyDown(int keyCode, KeyEvent event)  
{
     if (keyCode == KeyEvent.KEYCODE_BACK && event.getRepeatCount() == 0)
     {
        this.moveTaskToBack(true);
        return true;
     }
    return super.onKeyDown(keyCode, event);
}

If you want to close the activity use this.finish() method to close the current running activity. instead of this.moveTaskToBack(true);