标签：定时器
这是一个简单的定时器，分别为3S，5S和10S。倒计时的过程中，界面上会显示数字，数字的显示用了一些渐变动画，效果看起来还不错。
这个程序是自己写的，所以只是在UI线程中做的，实际项目上使用肯定需要不断完善。
xml代码如下：
<span style="font-family:SimSun;font-size:14px;"><span style="font-family:SimSun;font-size:14px;"><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".MainActivity"
android:background="@android:color/background_dark" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="@+id/timer_three_second"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="3S倒计时"/>
<Button
android:id="@+id/timer_five_second"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="5S倒计时"/>
<Button
android:id="@+id/timer_ten_second"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="10S倒计时"/>
</LinearLayout>
<LinearLayout
android:id="@+id/timer_root_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:layout_marginTop="100dp" >
</LinearLayout>
</LinearLayout></span></span>Java代码如下：
<span style="font-family:SimSun;font-size:14px;"><span style="font-family:SimSun;font-size:14px;">package com.jackie.timer;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.animation.AlphaAnimation;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.ScaleAnimation;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.Toast;
public class MainActivity extends ActionBarActivity implements View.OnClickListener {
private LinearLayout mTimerRootView;
private Button mThreeBtn;
private Button mFiveBtn;
private Button mTenBtn;
private ImageView mTimerView;
private AnimationSet mAnimationSet;
//用来记录倒计时的时间
private int mCurrentValue = 0;
private final int SECOND_1 = 1000;
/**
* @fields TIMER_ICON_IDS : TODO 倒计时事件图片
*/
public static final int[] TIMER_ICON_IDS = new int[]{
0, //从1开始，没有0
R.drawable.camera_timer_icon_1,
R.drawable.camera_timer_icon_2,
R.drawable.camera_timer_icon_3,
R.drawable.camera_timer_icon_4,
R.drawable.camera_timer_icon_5,
R.drawable.camera_timer_icon_6,
R.drawable.camera_timer_icon_7,
R.drawable.camera_timer_icon_8,
R.drawable.camera_timer_icon_9,
R.drawable.camera_timer_icon_10,
};
private static final int MSG_UPDATE_TIMER_VALUE = 0;
private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_UPDATE_TIMER_VALUE:
remindTimeValue();
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mTimerRootView = (LinearLayout) findViewById(R.id.timer_root_view);
mThreeBtn = (Button) findViewById(R.id.timer_three_second);
mFiveBtn = (Button) findViewById(R.id.timer_five_second);
mTenBtn = (Button) findViewById(R.id.timer_ten_second);
mThreeBtn.setOnClickListener(this);
mFiveBtn.setOnClickListener(this);
mTenBtn.setOnClickListener(this);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.timer_three_second:
mCurrentValue = 3;
break;
case R.id.timer_five_second:
mCurrentValue = 5;
break;
case R.id.timer_ten_second:
mCurrentValue = 10;
break;
}
mHandler.sendEmptyMessage(MSG_UPDATE_TIMER_VALUE);
}
private void remindTimeValue() {
if (mCurrentValue <= 0) {
Toast.makeText(this, "倒计时结束", Toast.LENGTH_LONG).show();
} else {
//更新界面
showTimerRemind();
mCurrentValue--;
//每个1S再发送消息
mHandler.sendEmptyMessageDelayed(MSG_UPDATE_TIMER_VALUE, SECOND_1);
}
}
private void showTimerRemind() {
runOnUiThread(new Runnable() {
@Override
public void run() {
//创建倒计时显示的View
creatTimerView();
//创建动画
initAnimation();
if(mCurrentValue > 0 && mCurrentValue < TIMER_ICON_IDS.length){
//【功能说明】该方法用于设置一个动画效果执行完毕后，View对象保留在终止的位置。
// 该方法的执行，需要首先通过setFillEnabled方法使能填充效果，否则设置无效。
mAnimationSet.setFillAfter(true);
mTimerView.setImageDrawable(getDrawable(TIMER_ICON_IDS[mCurrentValue]));
mTimerView.setVisibility(View.VISIBLE);
mTimerView.startAnimation(mAnimationSet);
}
}
});
}
private void creatTimerView() {
if(mTimerView == null) {
mTimerView = new ImageView(MainActivity.this);
mTimerRootView.addView(mTimerView);
}
}
private void initAnimation() {
ScaleAnimation mScale = new ScaleAnimation(1.0f, 0.5f, //X from 1 to 0.5
1.0f, 0.5f, //Y from 1 to 0.5
Animation.RELATIVE_TO_SELF, 0.5f,
Animation.RELATIVE_TO_SELF, 0.5f);
AlphaAnimation mAlpha = new AlphaAnimation(0f, 1f);
mAnimationSet = new AnimationSet(true);
mAnimationSet.addAnimation(mScale);
mAnimationSet.addAnimation(mAlpha);
mAnimationSet.setDuration(600);
mAnimationSet.setAnimationListener(new Animation.AnimationListener() {
@Override
public void onAnimationStart(Animation animation) {
if(mTimerView != null){
mTimerView.setVisibility(View.INVISIBLE);
mAnimationSet.setFillAfter(false);
}
}
@Override
public void onAnimationEnd(Animation animation) {
}
@Override
public void onAnimationRepeat(Animation animation) {
}
});
mAnimationSet.setFillAfter(true);
}
}</span></span>效果如下：
由于数字的变化有个渐变的过程，所以不太好截图，具体效果大家可以看真机。
其次这个程序没有考虑到一些case，比如，在倒计时的过程中，就不允许再点击按钮等等。
标签：定时器
原文地址：http://blog.csdn.net/shineflowers/article/details/44754061
