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Android helper class for showing cheat sheets (tooltips) for icon-only UI elements on long-press. This is already default platform behavior for icon-only action bar items and tabs. This class provides this behavior for any other such UI element.

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CheatSheet.java
Java
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/*
* Copyright 2012 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
 
package com.example.android.cheatsheet;
 
import android.content.Context;
import android.graphics.Rect;
import android.text.TextUtils;
import android.view.Gravity;
import android.view.View;
import android.widget.Toast;
 
/**
* Helper class for showing cheat sheets (tooltips) for icon-only UI elements on long-press. This is
* already default platform behavior for icon-only {@link android.app.ActionBar} items and tabs.
* This class provides this behavior for any other such UI element.
*
* <p>Based on the original action bar implementation in <a href="https://android.googlesource.com/platform/frameworks/base/+/refs/heads/master/core/java/com/android/internal/view/menu/ActionMenuItemView.java">
* ActionMenuItemView.java</a>.
*/
public class CheatSheet {
/**
* The estimated height of a toast, in dips (density-independent pixels). This is used to
* determine whether or not the toast should appear above or below the UI element.
*/
private static final int ESTIMATED_TOAST_HEIGHT_DIPS = 48;
 
/**
* Sets up a cheat sheet (tooltip) for the given view by setting its {@link
* android.view.View.OnLongClickListener}. When the view is long-pressed, a {@link Toast} with
* the view's {@link android.view.View#getContentDescription() content description} will be
* shown either above (default) or below the view (if there isn't room above it).
*
* @param view The view to add a cheat sheet for.
*/
public static void setup(View view) {
view.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
return showCheatSheet(view, view.getContentDescription());
}
});
}
 
/**
* Sets up a cheat sheet (tooltip) for the given view by setting its {@link
* android.view.View.OnLongClickListener}. When the view is long-pressed, a {@link Toast} with
* the given text will be shown either above (default) or below the view (if there isn't room
* above it).
*
* @param view The view to add a cheat sheet for.
* @param textResId The string resource containing the text to show on long-press.
*/
public static void setup(View view, final int textResId) {
view.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
return showCheatSheet(view, view.getContext().getString(textResId));
}
});
}
 
/**
* Sets up a cheat sheet (tooltip) for the given view by setting its {@link
* android.view.View.OnLongClickListener}. When the view is long-pressed, a {@link Toast} with
* the given text will be shown either above (default) or below the view (if there isn't room
* above it).
*
* @param view The view to add a cheat sheet for.
* @param text The text to show on long-press.
*/
public static void setup(View view, final CharSequence text) {
view.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
return showCheatSheet(view, text);
}
});
}
 
/**
* Removes the cheat sheet for the given view by removing the view's {@link
* android.view.View.OnLongClickListener}.
*
* @param view The view whose cheat sheet should be removed.
*/
public static void remove(final View view) {
view.setOnLongClickListener(null);
}
 
/**
* Internal helper method to show the cheat sheet toast.
*/
private static boolean showCheatSheet(View view, CharSequence text) {
if (TextUtils.isEmpty(text)) {
return false;
}
 
final int[] screenPos = new int[2]; // origin is device display
final Rect displayFrame = new Rect(); // includes decorations (e.g. status bar)
view.getLocationOnScreen(screenPos);
view.getWindowVisibleDisplayFrame(displayFrame);
 
final Context context = view.getContext();
final int viewWidth = view.getWidth();
final int viewHeight = view.getHeight();
final int viewCenterX = screenPos[0] + viewWidth / 2;
final int screenWidth = context.getResources().getDisplayMetrics().widthPixels;
final int estimatedToastHeight = (int) (ESTIMATED_TOAST_HEIGHT_DIPS
* context.getResources().getDisplayMetrics().density);
 
Toast cheatSheet = Toast.makeText(context, text, Toast.LENGTH_SHORT);
boolean showBelow = screenPos[1] < estimatedToastHeight;
if (showBelow) {
// Show below
// Offsets are after decorations (e.g. status bar) are factored in
cheatSheet.setGravity(Gravity.TOP | Gravity.CENTER_HORIZONTAL,
viewCenterX - screenWidth / 2,
screenPos[1] - displayFrame.top + viewHeight);
} else {
// Show above
// Offsets are after decorations (e.g. status bar) are factored in
// NOTE: We can't use Gravity.BOTTOM because when the keyboard is up
// its height isn't factored in.
cheatSheet.setGravity(Gravity.TOP | Gravity.CENTER_HORIZONTAL,
viewCenterX - screenWidth / 2,
screenPos[1] - displayFrame.top - estimatedToastHeight);
}
 
cheatSheet.show();
return true;
}
}

@romannurik, i was using it inside a view in a gridviewadapter. When using it, it was showing the tooltip properly. But the itemclicklistener was not getting called. Below is my GridViewAdapters code which extends BaseAdapter

public View getView(int position, View convertView, ViewGroup parent) {

        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        View gridView;
        if (convertView == null) {
            gridView = new View(context);
            gridView = inflater.inflate(R.layout.gridview, null);
            // set image based on selected text
            ImageView imageView = (ImageView) gridView
                    .findViewById(R.id.grid_item_image);
            String gridItemPosition = griditemValues[position];
            if (gridItemPosition.equals("a")) {
                imageView.setImageResource(R.drawable.printer_normal);
                imageView.setContentDescription("tooltip description");

                ButtonTooltipHelper.setup(imageView);
            } 
        } else {
            gridView = convertView;
        }       
        return gridView;
    }

Any help would be appreciated. Thanks

Anyone have a screenshot of what this looks like?

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