动画执行问题

This topic created in 4167 days ago, the information mentioned may be changed or developed.

========================代码一========================

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_anim);

dotImg = (ImageView) findViewById(R.id.anim_dotimg);
btn = (Button) findViewById(R.id.anim_btn);

btn.setOnClickListener(new Button.OnClickListener() {
    @Override
    public void onClick(View v) {
        AlphaAnimation alphaAnim = new AlphaAnimation(0.5f, 1f);
        alphaAnim.setDuration(2000);
        dotImg.setAnimation(alphaAnim);
        alphaAnim.start();

        Log.d("test", "start anim");
    }
});

}

========================代码一========================

========================代码二========================

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_anim);

dotImg = (ImageView) findViewById(R.id.anim_dotimg);
btn = (Button) findViewById(R.id.anim_btn);

btn.setOnClickListener(new Button.OnClickListener() {
    @Override
    public void onClick(View v) {
        AlphaAnimation alphaAnim = new AlphaAnimation(0.5f, 1f);
        alphaAnim.setDuration(2000);
        dotImg.startAnimation(alphaAnim);

        Log.d("test", "start anim");
    }
});

}

========================代码二========================

Q1：为何代码一动画无效果？或者说不执行？
Q2：有些文章说，更新UI必须在UI主线程。那么请问一些事件，如Click、Destroy等，我如何分辨哪些事件并不是UI主线程在执行呢？

alphaanim

void

代码

5 replies • 2015-06-16 15:15:03 +08:00