通过在android中按菜单项来更改背景图像

Question

我在android中创建简单的记事本应用程序，在选项菜单中我有＆＃34;更改背景＆＃34;作为一个菜单项，当用户点击它时，我只想更改背景图像[例如，我想将我的背景图像从efil塔更改为tajmahal]，我有10个图像在drawable ..如何随机更改它当每次用户点击＆＃34;更改背景＆＃34; option.Thank you。

Answer 1

int images[] = {R.drawable.eifel,R.drawable.tajmahal};
LinearLayout backLayout;

onCreate(Bundle savedInstanceState) {
   backLayout = (LinearLayout) findViewById(R.id.mybackgroundlayout);
}

private void changeBackground(){
 backLayout.setBackgroundResource(images[randInt(0,images.length-1)]);
}

public static int randInt(int min, int max) {
 Random rand = new Random();
 int randomNum = rand.nextInt((max - min) + 1) + min;
 return randomNum;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
    case R.id.changebackground:
        changeBackground();
        break;
    }
    return true;
}