Android：文字淡入淡出

本文介绍了Android：文字淡入淡出的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我已经阅读了这个stackoverflow问题和答案，并尝试实现文本淡入和淡出：

I've read this stackoverflow question and answer and tried to implement a text fade in and out:

如何在Android中淡入淡出文本？

这是我的实现：

public class ShowActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_show); final TextView mSwitcher = (TextView) findViewById(R.id.textFade); mSwitcher.setText("old text"); final Animation in = new AlphaAnimation(0.0f, 1.0f); in.setDuration(5000); final Animation out = new AlphaAnimation(1.0f, 0.0f); out.setDuration(5000); out.setAnimationListener(new AnimationListener() { @Override public void onAnimationEnd(Animation animation) { mSwitcher.setText("New Text"); mSwitcher.startAnimation(in); } @Override public void onAnimationRepeat(Animation arg0) { // TODO Auto-generated method stub } @Override public void onAnimationStart(Animation arg0) { // TODO Auto-generated method stub } }); mSwitcher.startAnimation(out); mSwitcher.setText("Text 1."); mSwitcher.startAnimation(in); mSwitcher.startAnimation(out); mSwitcher.setText("Text 2."); mSwitcher.startAnimation(in); } }

问题是，只有文字2出现，它只会淡入而不淡出。可能有什么问题？

The problem is, that only text 2 appears and it only fade in and not fade out. What could be wrong?

推荐答案

问题是你每次开始淡出动画时都会立即开始淡出动画。

The problem is that you are starting a fade in animation immediately every time you start a fade out animation.

我能够修改你的代码并得到一个简单的例子，这里是代码：

I was able to modify your code and get a simple example working, here's the code:

import android.os.Handler; public class ShowActivity extends Activity { Handler handler; TextView mSwitcher; Animation in; Animation out; int fadeCount; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_show); fadeCount = 0; handler = new Handler(); mSwitcher = (TextView) findViewById(R.id.textView); mSwitcher.setText("old text"); in = new AlphaAnimation(0.0f, 1.0f); in.setDuration(5000); out = new AlphaAnimation(1.0f, 0.0f); out.setDuration(5000); out.setAnimationListener(new Animation.AnimationListener() { @Override public void onAnimationEnd(Animation animation) { fadeCount++; if (fadeCount == 3){ mSwitcher.setText(""); Intent i = new Intent(getApplication() , MainActivity.class); startActivity(i); } else { if (fadeCount == 1) { mSwitcher.setText("Text 2."); } else { mSwitcher.setText("New Text"); } mSwitcher.startAnimation(in); handler.postDelayed(mFadeOut, 5000); } } @Override public void onAnimationRepeat(Animation arg0) { // TODO Auto-generated method stub } @Override public void onAnimationStart(Animation arg0) { // TODO Auto-generated method stub } }); //mSwitcher.startAnimation(out); mSwitcher.setText("Text 1."); mSwitcher.startAnimation(in); /* mSwitcher.startAnimation(out); mSwitcher.setText("Text 2."); mSwitcher.startAnimation(in); */ handler.postDelayed(mFadeOut, 5000); } private Runnable mFadeOut =new Runnable(){ @Override public void run() { //Speed up the last fade-out so that the Activity opens faster if (fadeCount == 2){ out.setDuration(2000); } mSwitcher.startAnimation(out); } }; }