Android开发中遇到的问题

一时失言乱红尘 2022-07-15 14:27 311阅读 0赞

本文转自“唯鹿”的博客，地址：

[http://blog.csdn.net/qq\_17766199/article/details/52661363][http_blog.csdn.net_qq_17766199_article_details_52661363]

1.App的首次安装。

问题描述：在我们安装完成一个app时，在安装界面直接点击打开。我们进入了app的首页，这时我们按home键返回桌面，再点击应用图标，会发现没有直接进入首页，而是先进入了app的闪屏页，在进入首页。重复这一步一直如此。这时我们按back键返回，发现没有直接退回桌面，而是返回到之前打开的多个首页。但是如果一开始安装完我们不是直接打开，而是在桌面点击应用进入就不会这样了。

奇奇怪怪~~

记得当时我在应用市场下载了部分应用，也有一些有同样的问题。但是有些虽然重复打开，但双击退出程序将整个重复打开的关闭了。这确实也是一种方法，但是觉得不是最合理。

解决方法：  
[https://code.google.com/p/android/issues/detail?id=2373\#c40][https_code.google.com_p_android_issues_detail_id_2373_c40]

[http://stackoverflow.com/questions/3042420/home-key-press-behaviour/4782423\#4782423][http_stackoverflow.com_questions_3042420_home-key-press-behaviour_4782423_4782423]

我贴一下代码

if (!isTaskRoot()) {
                Intent intent = getIntent();
                String action = intent.getAction();
                if (intent.hasCategory(Intent.CATEGORY_LAUNCHER) && action != null && action.equals(Intent.ACTION_MAIN)) {
                    finish();
                    return;
                }
            }

2.Android自定义CheckBox

问题描述：曾经写过一个自定义CheckBox，结果运行在4.1的手机上消失不见了。。。你说郁闷不。写法如下：

<?xml version="1.0" encoding="utf-8"?>
    <selector xmlns:android="http://schemas.android.com/apk/res/android">
        <item android:drawable="@drawable/icon_on" android:state_checked="true"/>
     
        <item android:drawable="@drawable/icon_off" android:state_checked="false"/>
     
    </selector>

写法没有什么问题吧，但是就是不显示，凭空消失。当然如果我加上文字，就出来了，但是文字图片重叠。。。

最后谷歌出了原因：大致是说4.1.2版本中CompoundButton没有getCompoundPaddingXX。两个版本的计算方式不一样，4.1.2以上版本绘制文字时，会把图片的宽度和paddingXX的宽度加上，而4.1.2版本只计算设置的paddingLeft。

知道了原因，解决方法：

1.  RecyclerView Bug

问题描述：这个是在友盟的错误分析中报的，错误信息如下：

java.lang.IndexOutOfBoundsException: Inconsistency detected. Invalid view holder adapter positionViewHolder{
       42fb7f40 position=11 id=-1, oldPos=-1, pLpos:-1 no parent}
        at android.support.v7.widget.RecyclerView$Recycler.validateViewHolderForOffsetPosition(RecyclerView.java:4801)
        at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4932)
        at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4913)
        at android.support.v7.widget.LinearLayoutManager$LayoutState.next(LinearLayoutManager.java:2029)
        at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1414)
        at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1377)
        at android.support.v7.widget.LinearLayoutManager.scrollBy(LinearLayoutManager.java:1193)
        at android.support.v7.widget.LinearLayoutManager.scrollVerticallyBy(LinearLayoutManager.java:1043)
        at android.support.v7.widget.RecyclerView.scrollByInternal(RecyclerView.java:1552)
        at android.support.v7.widget.RecyclerView.onTouchEvent(RecyclerView.java:2649)
        at android.view.View.dispatchTouchEvent(View.java:7706)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2224)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1954)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)
        at android.view.ViewGroup.dispatchTransformedTouchEvent(ViewGroup.java:2230)
        at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:1968)
        at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:2074)
        at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1521)
        at android.app.Activity.dispatchTouchEvent(Activity.java:2569)
        at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:2022)
        at android.view.View.dispatchPointerEvent(View.java:7886)
        at android.view.ViewRootImpl$ViewPostImeInputStage.processPointerEvent(ViewRootImpl.java:3967)
        at android.view.ViewRootImpl$ViewPostImeInputStage.onProcess(ViewRootImpl.java:3846)
        at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3412)
        at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3462)
        at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3431)
        at android.view.ViewRootImpl$AsyncInputStage.forward(ViewRootImpl.java:3538)
        at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3439)
        at android.view.ViewRootImpl$AsyncInputStage.apply(ViewRootImpl.java:3595)
        at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3412)
        at android.view.ViewRootImpl$InputStage.onDeliverToNext(ViewRootImpl.java:3462)
        at android.view.ViewRootImpl$InputStage.forward(ViewRootImpl.java:3431)
        at android.view.ViewRootImpl$InputStage.apply(ViewRootImpl.java:3439)
        at android.view.ViewRootImpl$InputStage.deliver(ViewRootImpl.java:3412)
        at android.view.ViewRootImpl.deliverInputEvent(ViewRootImpl.java:5552)
        at android.view.ViewRootImpl.doProcessInputEvents(ViewRootImpl.java:5532)
        at android.view.ViewRootImpl.enqueueInputEvent(ViewRootImpl.java:5503)
        at android.view.ViewRootImpl$WindowInputEventReceiver.onInputEvent(ViewRootImpl.java:5632)
        at android.view.InputEventReceiver.dispatchInputEvent(InputEventReceiver.java:185)
        at android.view.InputEventReceiver.nativeConsumeBatchedInputEvents(Native Method)
        at android.view.InputEventReceiver.consumeBatchedInputEvents(InputEventReceiver.java:176)
        at android.view.ViewRootImpl.doConsumeBatchedInput(ViewRootImpl.java:5605)
        at android.view.ViewRootImpl$ConsumeBatchedInputRunnable.run(ViewRootImpl.java:5651)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:761)
        at android.view.Choreographer.doCallbacks(Choreographer.java:574)
        at android.view.Choreographer.doFrame(Choreographer.java:542)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:747)
        at android.os.Handler.handleCallback(Handler.java:733)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:136)
        at android.app.ActivityThread.main(ActivityThread.java:5162)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:515)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:789)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:602)

从上面可以看到并没有报到我们自己的代码里面来，这就很尴尬了。老办法谷歌，找到了Drakeet大神的一篇[博客][Link 1]，说到了我的心坎里。

重现的方法是：使用 RecyclerView 加官方下拉刷新的时候，如果绑定的 List 对象在更新数据之前进行了 clear，而这时用户紧接着迅速上滑 RV，就会造成崩溃，而且异常不会报到你的代码上，属于RV内部错误。初次猜测是，当你 clear 了 list 之后，这时迅速上滑，而新数据还没到来，导致 RV 要更新加载下面的 Item 时候，找不到数据源了，造成 crash.

真是一样一样的，那么解决方法大神也提供了，就是在刷新，也就是 clear 的同时，让 RecyclerView 暂时不能够滑动，之后再允许滑动即可。代码就是在 RecyclerView 初始化的时候加上是否在刷新进而拦截手势：

mRecyclerView.setOnTouchListener(
            new View.OnTouchListener() {
                @Override
                public boolean onTouch(View v, MotionEvent event) {
                    if (mIsRefreshing) {
                        return true;
                    } else {
                        return false;
                    }
                }
            }
    );

当然如果觉得刷新时不能滑动可以用这种[方案][Link 2]：

public class WrapContentLinearLayoutManager extends LinearLayoutManager { 
        //... constructor
        @Override
        public void onLayoutChildren(RecyclerView.Recycler recycler, RecyclerView.State state) {
            try {
                super.onLayoutChildren(recycler, state);
            } catch (IndexOutOfBoundsException e) {
                Log.e("probe", "meet a IOOBE in RecyclerView");
            }
        }
    }

使用：

RecyclerView recyclerView = (RecyclerView)findViewById(R.id.recycler_view);
    
    recyclerView.setLayoutManager(new WrapContentLinearLayoutManager(activity, LinearLayoutManager.HORIZONTAL, false));

补充：但是这里要注意的是，禁止 RecycleView “下拉刷新” 和 “加载更多” 同时执行 。否则会报：

java.lang.IllegalStateException: Added View has RecyclerView as parent but view is not a real child. Unfiltered index:0
        at android.support.v7.widget.RecyclerView$LayoutManager.addViewInt(RecyclerView.java:7048)
        at android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:7012)
        at android.support.v7.widget.RecyclerView$LayoutManager.addView(RecyclerView.java:7000)
        at android.support.v7.widget.LinearLayoutManager.layoutChunk(LinearLayoutManager.java:1428)
        at android.support.v7.widget.LinearLayoutManager.fill(LinearLayoutManager.java:1377)
        at android.support.v7.widget.LinearLayoutManager.onLayoutChildren(LinearLayoutManager.java:578)
        at com.jingzhao.shopping.customview.WrapContentLinearLayoutManager.onLayoutChildren(WrapContentLinearLayoutManager.java:27)<---这里
        at android.support.v7.widget.RecyclerView.dispatchLayoutStep2(RecyclerView.java:3260)
        at android.support.v7.widget.RecyclerView.dispatchLayout(RecyclerView.java:3069)
        at android.support.v7.widget.RecyclerView.onLayout(RecyclerView.java:3518)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1077)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.support.v4.widget.SwipeRefreshLayout.onLayout(SwipeRefreshLayout.java:598)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703)
        at android.widget.LinearLayout.layoutHorizontal(LinearLayout.java:1692)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1468)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.widget.RelativeLayout.onLayout(RelativeLayout.java:1077)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1703)
        at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1557)
        at android.widget.LinearLayout.onLayout(LinearLayout.java:1466)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.widget.FrameLayout.layoutChildren(FrameLayout.java:579)
        at android.widget.FrameLayout.onLayout(FrameLayout.java:514)
        at android.view.View.layout(View.java:15697)
        at android.view.ViewGroup.layout(ViewGroup.java:5050)
        at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:2232)
        at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1984)
        at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1163)
        at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:6190)
        at android.view.Choreographer$CallbackRecord.run(Choreographer.java:773)
        at android.view.Choreographer.doCallbacks(Choreographer.java:586)
        at android.view.Choreographer.doFrame(Choreographer.java:556)
        at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:759)
        at android.os.Handler.handleCallback(Handler.java:739)
        at android.os.Handler.dispatchMessage(Handler.java:95)
        at android.os.Looper.loop(Looper.java:159)
        at android.app.ActivityThread.main(ActivityThread.java:5540)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:372)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:964)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:759)

可以做类似的处理：

if(swipeRefreshLayout.isRefreshing()){ 
       return;
    }

4.一些注意点

（1）平时为了给apk瘦身，我们会对图片进行有损或无损的压缩。那我平时有用到的一个有损压缩网站tinypng，但是切记我们的9图不要压缩，不然会有问题。（这里顺便分享一个做9图的在线工具[http://inloop.github.io/shadow4android/][http_inloop.github.io_shadow4android]）

（2）Android的透明主题需谨慎使用。

（3）for循环不要把获得数量的代码写在循环当中：for(int i = 0; i <= list.size(); i ++)

（4）ListView的如果其宽度或高度被设置为wrap\_content，会有性能等问题。参见：[http://stackoverflow.com/questions/4270278/layout-width-of-a-listview][http_stackoverflow.com_questions_4270278_layout-width-of-a-listview]

[http_blog.csdn.net_qq_17766199_article_details_52661363]: http://blog.csdn.net/qq_17766199/article/details/52661363
[https_code.google.com_p_android_issues_detail_id_2373_c40]: https://code.google.com/p/android/issues/detail?id=2373#c40
[http_stackoverflow.com_questions_3042420_home-key-press-behaviour_4782423_4782423]: http://stackoverflow.com/questions/3042420/home-key-press-behaviour/4782423#4782423
[Link 1]: https://drakeet.me/recyclerview-bug-indexoutofboundsexception-inconsistency-detected-invalid-item-position-solution?utm_source=tuicool&utm_medium=referral
[Link 2]: http://stackoverflow.com/questions/31759171/recyclerview-and-java-lang-indexoutofboundsexception-inconsistency-detected-in
[http_inloop.github.io_shadow4android]: http://inloop.github.io/shadow4android/
[http_stackoverflow.com_questions_4270278_layout-width-of-a-listview]: http://stackoverflow.com/questions/4270278/layout-width-of-a-listview