android postDelayed 方法不起作用

Question

我正在尝试为我的应用制作启动画面。我使用了 postDelayed 方法。这是我的代码:

   public class SplashScreenActivity extends Activity {

    private static final int SPLASH_DURATION_MS = 1500;

    private static final String TAG = SplashScreenActivity.class.getSimpleName();

    private Handler mHandler = new Handler();

    public static final int sdkVersion = Build.VERSION.SDK_INT;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.splash_screen);

        Random r = new Random();
        int imageNumber = r.nextInt(2 - 0) + 0;

        ImageView splashScreenBackground = (ImageView)findViewById(R.id.splash_screen_image);
        switch (imageNumber){
            case 0:
                if(sdkVersion > 20)
                    splashScreenBackground.setBackground(getDrawable(R.drawable.splash_screen_back));
                else
                    splashScreenBackground.setBackgroundDrawable(getResources().getDrawable(R.drawable.splash_screen_back));
                return;
            case 1:
                if(sdkVersion > 20)
                    splashScreenBackground.setBackground(getDrawable(R.drawable.buffon));
                else
                    splashScreenBackground.setBackgroundDrawable(getResources().getDrawable(R.drawable.buffon));
                return;
        }

        mHandler.postDelayed(mEndSplash, SPLASH_DURATION_MS);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        mEndSplash.run();
        return super.onTouchEvent(event);
    }

    private Runnable mEndSplash = new Runnable() {
        public void run() {
            if (!isFinishing()) {
                mHandler.removeCallbacks(this);

                Log.d(TAG, "Debugging before intent");
                startActivity(new Intent(
                        SplashScreenActivity.this, MainActivity.class
                ));
                Log.d(TAG, "Debugging after intent");
                finish();
            }
        };
    };

}

这是 onCreate 方法中的调用:

mHandler.postDelayed(mEndSplash, SPLASH_DURATION_MS);

问题是在我按下屏幕之前 Activity 不会改变。

另一件事，MainActivity 类已收费并显示了日志，但我没有在屏幕上看到它!!!我想知道是什么问题。谢谢

Answer 1

您在 switch 中使用 return 而不是 break，因此永远不会到达处理程序的代码。