In version 7.x, Token verification is added to Toast, which is true. However, when show() is called to display Toast, if a time-consuming operation gets stuck in the main thread for more than 5 seconds, BadTokenException exception will be thrown. At the beginning of 8.x system, Google will try catch internally. The 7.x system is a permanent pain, which can only be fixed by ourselves.
Repair plan I
Reflect the Context of the agent View, try catch within the Context, and deal with the badtokeneexception problem of Toast
. BadTokenListener, Toast throws a BadTokenException listener
publicinterface BadTokenListener {
/**
* Callback when Toast throws BadTokenException
*
* @param toast Toast instance with exception
*/
void onBadTokenCaught(@NonNull Toast toast);
}
. SafeToastContext, the Context used for wrapping Toast
publicclass SafeToastContext extends ContextWrapper {
private Toast mToast;
private BadTokenListener mBadTokenListener;
public SafeToastContext(Context base, Toast toast) {
super(base);
mToast = toast;
}
public void setBadTokenListener(@NonNull BadTokenListener badTokenListener) {
mBadTokenListener = badTokenListener;
}
@Override
public Context getApplicationContext() {
//Proxy original Context
returnnew ApplicationContextWrapper(super.getApplicationContext());
}
privateclass ApplicationContextWrapper extends ContextWrapper {
public ApplicationContextWrapper(Context base) {
super(base);
}
@Override
public Object getSystemService(String name) {
if (Context.WINDOW_SERVICE.equals(name)) {
//Get the original WindowManager and give it to WindowManagerWrapper agent to catch BadTokenException exception
Context baseContext = getBaseContext();
returnnew WindowManagerWrapper((WindowManager) baseContext.getSystemService(name));
}
returnsuper.getSystemService(name);
}
}
privateclass WindowManagerWrapper implements WindowManager {
/**
* Wrapped WindowManager instance
*/
private WindowManager mImpl;
public WindowManagerWrapper(@NonNull WindowManager readImpl) {
mImpl = readImpl;
}
@Override
public Display getDefaultDisplay() {
return mImpl.getDefaultDisplay();
}
@Override
public void removeViewImmediate(View view) {
mImpl.removeViewImmediate(view);
}
@Override
public void addView(View view, ViewGroup.LayoutParams params) {
//Use the tool in addView to catch BadTokenException exception
try {
mImpl.addView(view, params);
} catch (BadTokenException e) {
e.printStackTrace();
if (mBadTokenListener != null) {
mBadTokenListener.onBadTokenCaught(mToast);
}
}
}
@Override
public void updateViewLayout(View view, ViewGroup.LayoutParams params) {
mImpl.updateViewLayout(view, params);
}
@Override
public void removeView(View view) {
mImpl.removeView(view);
}
}
}
. ToastCompat, replacing Toast's facade
public class ToastCompat extends Toast {
private Toast mToast;
public ToastCompat(Context context, Toast toast) {
super(context);
mToast = toast;
}
public static ToastCompat makeText(Context context, CharSequence text, int duration) {
@SuppressLint("ShowToast")
Toast toast = Toast.makeText(context, text, duration);
setContextCompat(toast.getView(), context);
returnnew ToastCompat(context, toast);
}
public static Toast makeText(Context context, @StringRes int resId, int duration)
throws Resources.NotFoundException {
return makeText(context, context.getResources().getText(resId), duration);
}
public@NonNull
ToastCompat setBadTokenListener(@NonNull BadTokenListener listener) {
final Context context = getView().getContext();
if (context instanceof SafeToastContext) {
((SafeToastContext) context).setBadTokenListener(listener);
}
returnthis;
}
@Override
public void show() {
mToast.show();
}
@Override
public void setDuration(int duration) {
mToast.setDuration(duration);
}
@Override
public void setGravity(int gravity, int xOffset, int yOffset) {
mToast.setGravity(gravity, xOffset, yOffset);
}
@Override
public void setMargin(float horizontalMargin, float verticalMargin) {
mToast.setMargin(horizontalMargin, verticalMargin);
}
@Override
public void setText(int resId) {
mToast.setText(resId);
}
@Override
public void setText(CharSequence s) {
mToast.setText(s);
}
@Override
public void setView(View view) {
mToast.setView(view);
setContextCompat(view, new SafeToastContext(view.getContext(), this));
}
@Override
public float getHorizontalMargin() {
return mToast.getHorizontalMargin();
}
@Override
public float getVerticalMargin() {
return mToast.getVerticalMargin();
}
@Override
public int getDuration() {
return mToast.getDuration();
}
@Override
public int getGravity() {
return mToast.getGravity();
}
@Override
public int getXOffset() {
return mToast.getXOffset();
}
@Override
public int getYOffset() {
return mToast.getYOffset();
}
@Override
public View getView() {
return mToast.getView();
}
@NonNull
public Toast getBaseToast() {
return mToast;
}
/**
* Reflection sets the Context in View. Toast will get the Context of View to get WindowManager
*/
private static void setContextCompat(@NonNull View view, @NonNull Context context) {
//7.1.1
if (Build.VERSION.SDK_INT == 25) {
try {
Field field = View.class.getDeclaredField("mContext");
field.setAccessible(true);
field.set(view, context);
} catch (Throwable e) {
e.printStackTrace();
}
}
}
}
. use ToastCompat instead of Toast
ToastCompat.makeText(context,"I am Toast Content", Toast.LENGTH_SHORT)
.setBadTokenListener(toast ->
Logger.d("Toast: " + toast + " => Throw out BadTokenException abnormal")
)
.show();
Repair plan II
Hook Toast, replace the Handler of TN object in Toast, and try catch the method of dispatchMessage()
public class SafeToast {
privatestatic Field sField_TN;
privatestatic Field sField_TN_Handler;
static {
try {
//Reflection getting TN object
sField_TN = Toast.class.getDeclaredField("mTN");
sField_TN.setAccessible(true);
sField_TN_Handler = sField_TN.getType().getDeclaredField("mHandler");
sField_TN_Handler.setAccessible(true);
} catch (Exception e) {
e.printStackTrace();
}
}
private SafeToast() {
}
@SuppressLint("ShowToast")
public static void show(Context context, CharSequence message, int duration) {
show(context, message, duration, null);
}
@SuppressLint("ShowToast")
public static void show(Context context, CharSequence message, int duration, BadTokenListener badTokenListener) {
Toast toast = Toast.makeText(context.getApplicationContext(), message, duration);
hook(toast, badTokenListener);
toast.setDuration(duration);
toast.setText(message);
toast.show();
}
@SuppressLint("ShowToast")
public static void show(Context context, @StringRes int resId, int duration) {
show(context, resId, duration, null);
}
@SuppressLint("ShowToast")
public static void show(Context context, @StringRes int resId, int duration, BadTokenListener badTokenListener) {
Toast toast = Toast.makeText(context.getApplicationContext(), resId, duration);
hook(toast, badTokenListener);
toast.setDuration(duration);
toast.setText(context.getString(resId));
toast.show();
}
private static void hook(Toast toast, BadTokenListener badTokenListener) {
try {
Object tn = sField_TN.get(toast);
Handler originHandler = (Handler) sField_TN_Handler.get(tn);
sField_TN_Handler.set(tn, new SafeHandler(toast, originHandler, badTokenListener));
} catch (Throwable e) {
e.printStackTrace();
}
}
/**
* Replace Toast's original Handler
*/
privatestaticclass SafeHandler extends Handler {
private Toast mToast;
private Handler mOriginImpl;
private BadTokenListener mBadTokenListener;
SafeHandler(Toast toast, Handler originHandler, BadTokenListener badTokenListener) {
mToast = toast;
mOriginImpl = originHandler;
mBadTokenListener = badTokenListener;
}
@Override
public void dispatchMessage(Message msg) {
//Try catch the processing method of distributing Message
try {
super.dispatchMessage(msg);
} catch (WindowManager.BadTokenException e) {
e.printStackTrace();
if (mBadTokenListener != null) {
mBadTokenListener.onBadTokenCaught(mToast);
}
}
}
@Override
public void handleMessage(Message msg) {
//Need to delegate to the original Handler for execution
mOriginImpl.handleMessage(msg);
}
}
}
. use safeload instead of Toast
SafeToast.show(context,"I am Toast Content", Toast.LENGTH_SHORT, toast ->
Logger.d("Toast: " + toast + " => Throw out BadTokenException abnormal"));
