使用 ViewCacheStuffer 自定义弹幕样式偶现空指针错误

[mzw1004]

自定义布局中使用了 TextView ，在 workerthread 中进行 measure 时，会有概率出现空指针异常，版本为 0.8.3 ，错误日志如下：

java.lang.NullPointerException: Attempt to invoke virtual method 'int android.text.Layout.getLineCount()' on a null object reference
at android.widget.TextView.onMeasure(TextView.java:7312)
at android.view.View.measure(View.java:18948)
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:5976)
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1486)
at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1129)
at android.widget.LinearLayout.onMeasure(LinearLayout.java:649)
at android.view.View.measure(View.java:18948)
at master.flame.danmaku.danmaku.model.android.ViewCacheStuffer$ViewHolder.measure(ViewCacheStuffer.java:28)
at master.flame.danmaku.danmaku.model.android.ViewCacheStuffer.measure(ViewCacheStuffer.java:85)
at master.flame.danmaku.danmaku.model.android.AndroidDisplayer.measure(AndroidDisplayer.java:2526)
at master.flame.danmaku.danmaku.model.BaseDanmaku.measure(BaseDanmaku.java:235)
at master.flame.danmaku.danmaku.model.R2LDanmaku.measure(R2LDanmaku.java:113)
at master.flame.danmaku.controller.CacheManagingDrawTask$CacheManager$CacheHandler.a(CacheManagingDrawTask.java:865)
at master.flame.danmaku.controller.CacheManagingDrawTask$CacheManager$CacheHandler.a(CacheManagingDrawTask.java:939)
at master.flame.danmaku.controller.CacheManagingDrawTask$CacheManager$CacheHandler.handleMessage(CacheManagingDrawTask.java:550)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:150)
at android.os.HandlerThread.run(HandlerThread.java:61)

[zhangxq]

同学，我也遇到同样的问题，请问你解决了吗？如何解决的？谢谢

[mzw1004]

我放弃使用 ViewCacheStuffer 了，最后用自定义的 BaseCacheStuffer

[zhangxq]

哦，我刚想到可以重写ViewCacheStuffer的measure方法，自己做处理，比如加异常捕捉。

[chaichuanfa]

v0.9.12依然有这个问题，关注中

[pys200603027]

这个问题解决了嘛？

[zourb]

这个问题是必现吗，有复现步骤吗

[mzw1004]

@zourb 印象中不是必现，多添加几条弹幕会有概率出现。

[erleizh]

我也发现了

[jianglinair]

自定义 ViewHolder 继承 ViewCacheStuffer.ViewHolder 可以保持不崩，但崩溃原因没找到。代码如下：

    public static class MyViewHolder extends ViewCacheStuffer.ViewHolder {

        private final View mItemView;
        private final GradientTextView mGtvText;

        public MyViewHolder (View itemView) {
            super(itemView);
            mItemView = itemView;
            mGtvText = itemView.findViewById(R.id.gtv_danmaku_normal);
        }

        @Override
        public void measure(int widthMeasureSpec, int heightMeasureSpec) {
            try {
                super.measure(widthMeasureSpec, heightMeasureSpec);
            } catch (Exception e) {
                Log.d("[jianglin]", "MyViewHolder.measure: CRASH!");
                Log.d("[jianglin]", "MyViewHolder.measure: " + e.getMessage());
            }
        }
    }

[qinweiforandroid]

@jiangzhuoyan1984

你有没有发现有的时候会出现测量失败 System.err 的消息， 导致界面显示问题

[wygsqsj]

目前会在安卓12/13的机器上崩在系统底层,不知道是什么原因导致的

00 pc 0000000000054070 /apex/com.android.runtime/lib64/bionic/libc.so (abort+164) [arm64-v8a::25eadd32a5b6753e7e58e01ae8014530]

2

01 pc 00000000000429c4 /apex/com.android.runtime/lib64/bionic/libc.so (scudo::die()+8) [arm64-v8a::25eadd32a5b6753e7e58e01ae8014530]

3

02 pc 0000000000043070 /apex/com.android.runtime/lib64/bionic/libc.so (scudo::ScopedErrorReport::~ScopedErrorReport()+32) [arm64-v8a::25eadd32a5b6753e7e58e01ae8014530]

4

03 pc 00000000000433d0 /apex/com.android.runtime/lib64/bionic/libc.so (scudo::reportInvalidChunkState(scudo::AllocatorAction, void*)+116) [arm64-v8a::25eadd32a5b6753e7e58e01ae8014530]

5

04 pc 0000000000044bf0 /apex/com.android.runtime/lib64/bionic/libc.so (scudo::Allocator<scudo::AndroidConfig, &(scudo_malloc_postinit)>::deallocate(void*, scudo::Chunk::Origin, unsigned long, unsigned long)+308) [arm64-v8a::25eadd32a5b6753e7e58e01ae8014530]

6

05 pc 0000000000049de8 /system/lib64/libminikin.so (minikin::MeasuredData::boringLayoutUseMeasuredDataDoFLayout(minikin::U16StringPiece const&, float, bool, bool, bool)+164) [arm64-v8a::38ab8f36a7547b3d7bea60edded5d114]

7

06 pc 0000000000223470 /system/lib64/libhwui.so [arm64-v8a::fe97291d2f12507982da13e8bd49868a]

8

07 pc 00000000001f87f4 /system/framework/arm64/boot-framework.oat [arm64-v8a::80d8736761f18d681316a5ad36eacbc9]

9 java: 10 android.graphics.text.MeasuredData.boringLayoutUseMeasuredDataDoFLayout(MeasuredData.java:119) 11 android.graphics.Paint.boringLayoutUseMeasuredDataDoFLayout(Paint.java:3525) 12 android.text.BoringLayout.isBoring(BoringLayout.java:637) 13 android.widget.TextView.onMeasure(TextView.java:10231) 14 androidx.appcompat.widget.AppCompatTextView.onMeasure(TbsSdkJava:2) 15 android.view.View.measure(View.java:26980) 16 android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:7259) 17 android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1580) 18 android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1211) 19 android.widget.LinearLayout.onMeasure(LinearLayout.java:730) 20 android.view.View.measure(View.java:26980) 21 master.flame.danmaku.danmaku.model.android.k$a.e(TbsSdkJava:1)