AztecEditor-Android: Add a character before the picture in demo app crashes Aztec

This is weird. I tried to add some character before the first picture in demo app and Aztec crashed with the following stack trace:

                  java.lang.ArrayIndexOutOfBoundsException: length=39; index=-1
                      at android.text.DynamicLayout.getBlockIndex(DynamicLayout.java:646)
                      at android.widget.Editor.drawHardwareAccelerated(Editor.java:1787)
                      at android.widget.Editor.onDraw(Editor.java:1756)
                      at android.widget.TextView.onDraw(TextView.java:7723)
                      at android.view.View.draw(View.java:20338)
                      at android.view.View.updateDisplayListIfDirty(View.java:19283)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.updateDisplayListIfDirty(View.java:19274)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.draw(View.java:20341)
                      at android.widget.ScrollView.draw(ScrollView.java:2731)
                      at android.view.View.updateDisplayListIfDirty(View.java:19283)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.updateDisplayListIfDirty(View.java:19274)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.updateDisplayListIfDirty(View.java:19274)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.updateDisplayListIfDirty(View.java:19274)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.updateDisplayListIfDirty(View.java:19274)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.updateDisplayListIfDirty(View.java:19274)
                      at android.view.View.draw(View.java:20061)
                      at android.view.ViewGroup.drawChild(ViewGroup.java:4421)
                      at android.view.ViewGroup.dispatchDraw(ViewGroup.java:4207)
                      at android.view.View.draw(View.java:20341)
                      at com.android.internal.policy.DecorView.draw(DecorView.java:979)
                      at android.view.View.updateDisplayListIfDirty(View.java:19283)
                      at android.view.ThreadedRenderer.updateViewTreeDisplayList(ThreadedRenderer.java:686)
                      at android.view.ThreadedRenderer.updateRootDisplayList(ThreadedRenderer.java:692)
                      at android.view.ThreadedRenderer.draw(ThreadedRenderer.java:800)
                      at android.view.ViewRootImpl.draw(ViewRootImpl.java:3451)
                      at android.view.ViewRootImpl.performDraw(ViewRootImpl.java:3238)
                      at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:2773)
                      at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:1742)
                      at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:7763)
                      at android.view.Choreographer$CallbackRecord.run(Choreographer.java:911)
                      at android.view.Choreographer.doCallbacks(Choreographer.java:723)
                      at android.view.Choreographer.doFrame(Choreographer.java:658)
                      at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:897)
                      at android.os.Handler.handleCallback(Handler.java:789)
                      at android.os.Handler.dispatchMessage(Handler.java:98)
                      at android.os.Looper.loop(Looper.java:164)
                      at android.app.ActivityThread.main(ActivityThread.java:6938)
                      at java.lang.reflect.Method.invoke(Native Method)
                      at com.android.internal.os.Zygote$MethodAndArgsCaller.run(Zygote.java:327)
                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1374)

I’ve been able to reproduce the issue on Android 8.0 on both emulators, and real devices.

Steps to repro:

• Start the demo app
• Tap at the beginning of the document to show the keyboard up
• Tap a key
• Crash

Would be cool if someone else can verify this report, since looking at crash report it seems something internal to Android.

Tested on develop running on Android 8.0.