自定义Chronometer解决app切到后台Chronomet
2022-08-09 本文已影响0人
阡陌昏晨
问题
当APP切到后台时候,再切回来时候,发现时间还是切出去时候的时间,这是为什么呢?
原来:
当APP进入后台时,会调用onWindowVisibilityChanged()方法,Chronometer回调的onChronometer方法是通过dispatchChronometerTick()方法进行回调的,但是在updateRunning()方法中有一个running变量,这个变量进行了一个是否在显示在前台判断,所以在后台时并不会调用dispatchChronometerTick()方法
解决方法自定义Chronometer
package com.cias.vas.lib.widget.tv;
import android.annotation.SuppressLint;
import android.content.Context;
import android.os.Handler;
import android.os.Message;
import android.os.SystemClock;
import android.text.format.DateUtils;
import android.util.AttributeSet;
import android.view.accessibility.AccessibilityEvent;
import android.view.accessibility.AccessibilityNodeInfo;
import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.widget.AppCompatTextView;
import org.jetbrains.annotations.NotNull;
import java.util.Formatter;
import java.util.IllegalFormatException;
import java.util.Locale;
/**
* @Description:
* @Author: zhoudequn
* @CreateDate: 2022/5/16 15:12
*/
public class MyChronometer extends AppCompatTextView {
public interface OnChronometerTickListener {
void onChronometerTick(MyChronometer myChronometer);
}
private long mBase;
private boolean mVisible;
private boolean mStarted;
private boolean mRunning;
private boolean mLogged;
private String mFormat;
private Formatter mFormatter;
private Locale mFormatterLocale;
private Object[] mFormatterArgs = new Object[1];
private StringBuilder mFormatBuilder;
private OnChronometerTickListener mOnChronometerTickListener;
private StringBuilder mRecycle = new StringBuilder(8);
private static final int TICK_WHAT = 2;
public MyChronometer(@NonNull @NotNull Context context) {
super(context);
}
public MyChronometer(@NonNull @NotNull Context context, @Nullable @org.jetbrains.annotations.Nullable AttributeSet attrs) {
super(context, attrs);
}
public MyChronometer(@NonNull @NotNull Context context, @Nullable @org.jetbrains.annotations.Nullable AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
init();
}
private void init() {
mBase = SystemClock.elapsedRealtime();
updateText(mBase);
}
public void setBase(long base) {
mBase = base;
dispatchChronometerTick();
updateText(SystemClock.elapsedRealtime());
}
public long getBase() {
return mBase;
}
public void setFormat(String format) {
mFormat = format;
if (format != null && mFormatBuilder == null) {
mFormatBuilder = new StringBuilder(format.length() * 2);
}
}
public String getFormat() {
return mFormat;
}
public void setOnChronometerTickListener(OnChronometerTickListener listener) {
mOnChronometerTickListener = listener;
}
public OnChronometerTickListener getOnChronometerTickListener() {
return mOnChronometerTickListener;
}
public void start() {
mStarted = true;
updateRunning();
}
public void stop() {
mStarted = false;
updateRunning();
}
public void setStarted(boolean started) {
mStarted = started;
updateRunning();
}
@Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
mVisible = false;
updateRunning();
}
@Override
protected void onWindowVisibilityChanged(int visibility) {
super.onWindowVisibilityChanged(visibility);
updateRunning();
}
private synchronized void updateText(long now) {
long seconds = now - mBase;
seconds /= 1000;
String text = DateUtils.formatElapsedTime(mRecycle, seconds);
if (mFormat != null) {
Locale loc = Locale.getDefault();
if (mFormatter == null || !loc.equals(mFormatterLocale)) {
mFormatterLocale = loc;
mFormatter = new Formatter(mFormatBuilder, loc);
}
mFormatBuilder.setLength(0);
mFormatterArgs[0] = text;
try {
mFormatter.format(mFormat, mFormatterArgs);
text = mFormatBuilder.toString();
} catch (IllegalFormatException ex) {
if (!mLogged) {
mLogged = true;
}
}
}
setText(text);
}
private void updateRunning() {
boolean running = mStarted;
if (running != mRunning) {
if (running) {
updateText(SystemClock.elapsedRealtime());
dispatchChronometerTick();
mHandler.sendMessageDelayed(Message.obtain(mHandler, TICK_WHAT), 1000);
} else {
mHandler.removeMessages(TICK_WHAT);
}
mRunning = running;
}
}
private Handler mHandler = new Handler() {
public void handleMessage(Message m) {
if (mRunning) {
updateText(SystemClock.elapsedRealtime());
dispatchChronometerTick();
sendMessageDelayed(Message.obtain(this, TICK_WHAT), 1000);
}
}
};
void dispatchChronometerTick() {
if (mOnChronometerTickListener != null) {
mOnChronometerTickListener.onChronometerTick(this);
}
}
@SuppressLint("NewApi")
@Override
public void onInitializeAccessibilityEvent(AccessibilityEvent event) {
super.onInitializeAccessibilityEvent(event);
event.setClassName(MyChronometer.class.getName());
}
@SuppressLint("NewApi")
@Override
public void onInitializeAccessibilityNodeInfo(AccessibilityNodeInfo info) {
super.onInitializeAccessibilityNodeInfo(info);
info.setClassName(MyChronometer.class.getName());
}
}