选择textview后如何显示弹出窗口而不是CAB？ [英] How to display popup instead of CAB when textview is selected?
问题描述
我正在制作一个阅读应用程序，它具有全屏活动。
当用户选择文本的一部分时，会出现上下文操作栏带有复制选项。这是默认行为。但是此操作栏会阻止其下方的文本，因此用户无法选择它。
我想显示一个如下所示的弹出窗口。
我尝试从 onCreateActionMode 返回 false ，但是当我这样做时，我无法
我想知道是否有一种标准的方法来实现这一目标，因为许多阅读应用程序都使用这种设计。
我不知道Play图书如何实现这一目标，但是您可以创建
奖金-动画
因为我们知道 PopupWindow 的开始位置和偏移量随着选择的变化而变化，所以我们可以轻松地在两个值之间进行线性插值以创建一个不错的
public static float lerp（float a，float b，float v）{
返回a +（b-a）* v;
}
private static final int DEFAULT_ANIM_DUR = 350;
private static final int DEFAULT_ANIM_DELAY = 500;
@Override
public void onTextSelected（）{
final View popupContent = popupWindow.getContentView（）;
if（popupWindow.isShowing（））{
//计算更新的x / y弹出坐标
popupContent.getHandler（）。removeCallbacksAndMessages（null）;
popupContent.postDelayed（（）-> {
//弹出窗口的当前x / y位置
final int currx = currLoc.x;
final int curry = currLoc .y;
//计算更新后的x / y弹出坐标
最终Point ploc = calculatePopupLocation（）;
currLoc.set（ploc.x，ploc.y）;
//在当前和更新的弹出坐标之间进行线性插值
final ValueAnimator anim = ValueAnimator.ofFloat（0f，1f）;
anim.addUpdateListener（animation-> {
final float v =（ float）animation.getAnimatedValue（）;
final int x = Math.round（AnimUtils.lerp（currx，ploc.x，v））;
final int y = Math.round（AnimUtils.lerp（ curry，ploc.y，v））;
popupWindow.update（x，y，DEFAULT_WIDTH，DEFAULT_HEIGHT）;
}）;
anim.setDuration（DEFAULT_ANIM_DUR）;
ani m.start（）;
}，DEFAULT_ANIM_DELAY）；
} else {
...
}
}
Results
$b$ b
Extra
I don't go into how to attach on click listeners to the popup actions and there are probably several ways to achieve this same effect with different calculations and implementations. But I will mention that if you wanted to retrieve the selected text and then do something with it, you’d just need to CharSequence.subSequence the min and max from the selected text.
Anyway, I hope this has been helpful! Let me know if you have any questions.
I am making a reading app and it has a full screen activity.
When user selects the part of the text a contextual action bar appears with option of copy. This is the default behaviour. But this actionbar blocks the text under it so user cannot select it.
I want to show a popup window like below.
I tried returning false from onCreateActionMode but when i do this i can't select the text either.
I want to know if there is a standart way to achieve this as many reading applications use this design.
I don't know how Play Books achieves this, but you could create a PopupWindow and calculate where to position it based on the selected text using Layout.getSelectionPath and a little bit of math. Basically, we're going to:
- Calculate the bounds of the selected text
- Calculate the bounds and initial location of the
PopupWindow - Calculate the difference between the two
- Offset the
PopupWindowto rest center horizontally/vertically above or below the selected text
Calculating the selection bounds
Fills in the specified Path with a representation of a highlight between the specified offsets. This will often be a rectangle or a potentially discontinuous set of rectangles. If the start and end are the same, the returned path is empty.
So, the specified offsets in our case would be the start and end of the selection, which can be found using Selection.getSelectionStart and Selection.getSelectionEnd. For convenience, TextView gives us TextView.getSelectionStart, TextView.getSelectionEnd and TextView.getLayout.
final Path selDest = new Path();
final RectF selBounds = new RectF();
final Rect outBounds = new Rect();
// Calculate the selection start and end offset
final int selStart = yourTextView.getSelectionStart();
final int selEnd = yourTextView.getSelectionEnd();
final int min = Math.max(0, Math.min(selStart, selEnd));
final int max = Math.max(0, Math.max(selStart, selEnd));
// Calculate the selection outBounds
yourTextView.getLayout().getSelectionPath(min, max, selDest);
selDest.computeBounds(selBounds, true /* this param is ignored */);
selBounds.roundOut(outBounds);
Now that we have a Rect of the selected text bounds, we can choose where we want to place the PopupWindow relative to it. In this case, we'll center it horizontally along the top or bottom of the selected text, depending on how much space we have to display our popup.
Calculating the initial popup coordinates
Next we'll need to calculate the bounds of the popup content. To do this, we'll first need to call PopupWindow.showAtLocation, but the bounds of the View we inflate won't immediately be available, so I'd recommend using a ViewTreeObserver.OnGlobalLayoutListener to wait for them to become available.
popupWindow.showAtLocation(yourTextView, Gravity.TOP, 0, 0)
PopupWindow.showAtLocation requires:
- A
Viewto retrieve a validWindowtoken from, which just uniquely identifies theWindowto place the popup in - An optional gravity, but in our case it'll be
Gravity.TOP - Optional x/y offsets
Since we can't determine the x/y offset until the popup content is laid out, we'll just initially place it at the default location. If you try to call PopupWindow.showAtLocation before the View you pass in has been laid out, you'll receive a WindowManager.BadTokenException, so you may consider using a ViewTreeObserver.OnGlobalLayoutListener to avoid that, but it mostly comes up when you have text selected and rotate your device.
final Rect cframe = new Rect();
final int[] cloc = new int[2];
popupContent.getLocationOnScreen(cloc);
popupContent.getLocalVisibleRect(cbounds);
popupContent.getWindowVisibleDisplayFrame(cframe);
final int scrollY = ((View) yourTextView.getParent()).getScrollY();
final int[] tloc = new int[2];
yourTextView.getLocationInWindow(tloc);
final int startX = cloc[0] + cbounds.centerX();
final int startY = cloc[1] + cbounds.centerY() - (tloc[1] - cframe.top) - scrollY;
View.getLocationOnScreenwill return us the x/y coordinates for the popup content.View.getLocalVisibleRectwill return us the bounds of the popup contentView.getWindowVisibleDisplayFramewill return us the offsets to accommodate for the action bar, if presentView.getScrollYwill return us theyoffset for whatever scroll container ourTextViewis in (ScrollViewin my case)View.getLocationInWindowwill return us theyoffset for ourTextView, in case the action bar pushes it down a little
Once we've gotten all of the info we need, we can calculate the final starting x/y of the popup content and then use this to figure out the difference between them and the selected text Rect so we can PopupWindow.update to the new location.
Calculating the offset popup coordinates
// Calculate the top and bottom offset of the popup relative to the selection bounds
final int popupHeight = cbounds.height();
final int textPadding = yourTextView.getPaddingLeft();
final int topOffset = Math.round(selBounds.top - startY);
final int btmOffset = Math.round(selBounds.bottom - (startY - popupHeight));
// Calculate the x/y coordinates for the popup relative to the selection bounds
final int x = Math.round(selBounds.centerX() + textPadding - startX);
final int y = Math.round(selBounds.top - scrollY < startY ? btmOffset : topOffset);
If there's enough room to display the popup above the selected text, we'll put it there; otherwise, we'll offset it below the selected text. In my case, I have 16dp padding around my TextView, so that needs to be taken into account too. We'll end up with the final x and y location to offset the PopupWindow with.
popupWindow.update(x, y, -1, -1);
-1 here just represents the default width/height for we supplied for the PopupWindow, in our case it'll be ViewGroup.LayoutParams.WRAP_CONTENT
Listening for selection changes
We want the PopupWindow to update every time we change the selected text.
An easy way to listen for selection changes is to subclass TextView and provide a callback to TextView.onSelectionChanged.
public class NotifyingSelectionTextView extends AppCompatTextView {
private SelectionChangeListener listener;
public NotifyingSelectionTextView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onSelectionChanged(int selStart, int selEnd) {
super.onSelectionChanged(selStart, selEnd);
if (listener != null) {
if (hasSelection()) {
listener.onTextSelected();
} else {
listener.onTextUnselected();
}
}
}
public void setSelectionChangeListener(SelectionChangeListener listener) {
this.listener = listener;
}
public interface SelectionChangeListener {
void onTextSelected();
void onTextUnselected();
}
}
Listening for scroll changes
If you have a TextView in a scroll container like ScrollView, you may also want to listen for scroll changes so that you can anchor your popup while you're scrolling. An easy way to listen for those is to subclass ScrollView and provide a callback to View.onScrollChanged
public class NotifyingScrollView extends ScrollView {
private ScrollChangeListener listener;
public NotifyingScrollView(Context context, @Nullable AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onScrollChanged(int l, int t, int oldl, int oldt) {
super.onScrollChanged(l, t, oldl, oldt);
if (listener != null) {
listener.onScrollChanged();
}
}
public void setScrollChangeListener(ScrollChangeListener listener) {
this.listener = listener;
}
public interface ScrollChangeListener {
void onScrollChanged();
}
}
Creating an empty ActionMode.Callback
Like you mention in your post, we'll need to return true in ActionMode.Callback.onCreateActionMode in order for our text to remain selectable. But we'll also need to call Menu.clear in ActionMode.Callback.onPrepareActionMode in order to remove all the items you may find in an ActionMode for selected text.
/** An {@link ActionMode.Callback} used to remove all action items from text selection */
static final class EmptyActionMode extends SimpleActionModeCallback {
@Override
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
// Return true to ensure the text is still selectable
return true;
}
@Override
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
// Remove all action items to provide an actionmode-less selection
menu.clear();
return true;
}
}
Now we can use TextView.setCustomSelectionActionModeCallback to apply our custom ActionMode. SimpleActionModeCallback is a custom class that just provides stubs for ActionMode.Callback, kinda similar to ViewPager.SimpleOnPageChangeListener
public class SimpleActionModeCallback implements ActionMode.Callback {
@Override
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
return false;
}
@Override
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
return false;
}
@Override
public boolean onActionItemClicked(ActionMode mode, MenuItem item) {
return false;
}
@Override
public void onDestroyActionMode(ActionMode mode) {
}
}
Layouts
This is the Activity layout we're using:
<your.package.name.NotifyingScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/notifying_scroll_view"
android:layout_width="match_parent"
android:layout_height="match_parent">
<your.package.name.NotifyingSelectionTextView
android:id="@+id/notifying_text_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:padding="16dp"
android:textIsSelectable="true"
android:textSize="20sp" />
</your.package.name.NotifyingScrollView>
This is our popup layout:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="@drawable/action_mode_popup_bg"
android:orientation="vertical"
tools:ignore="ContentDescription">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageButton
android:id="@+id/view_action_mode_popup_add_note"
style="@style/ActionModePopupButton"
android:src="@drawable/ic_note_add_black_24dp" />
<ImageButton
android:id="@+id/view_action_mode_popup_translate"
style="@style/ActionModePopupButton"
android:src="@drawable/ic_translate_black_24dp" />
<ImageButton
android:id="@+id/view_action_mode_popup_search"
style="@style/ActionModePopupButton"
android:src="@drawable/ic_search_black_24dp" />
</LinearLayout>
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:layout_margin="8dp"
android:background="@android:color/darker_gray" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<ImageButton
android:id="@+id/view_action_mode_popup_red"
style="@style/ActionModePopupSwatch"
android:src="@drawable/round_red" />
<ImageButton
android:id="@+id/view_action_mode_popup_yellow"
style="@style/ActionModePopupSwatch"
android:src="@drawable/round_yellow" />
<ImageButton
android:id="@+id/view_action_mode_popup_green"
style="@style/ActionModePopupSwatch"
android:src="@drawable/round_green" />
<ImageButton
android:id="@+id/view_action_mode_popup_blue"
style="@style/ActionModePopupSwatch"
android:src="@drawable/round_blue" />
<ImageButton
android:id="@+id/view_action_mode_popup_clear_format"
style="@style/ActionModePopupSwatch"
android:src="@drawable/ic_format_clear_black_24dp"
android:visibility="gone" />
</LinearLayout>
</LinearLayout>
These are our popup button styles:
<style name="ActionModePopupButton">
<item name="android:layout_width">48dp</item>
<item name="android:layout_height">48dp</item>
<item name="android:layout_weight">1</item>
<item name="android:background">?selectableItemBackground</item>
</style>
<style name="ActionModePopupSwatch" parent="ActionModePopupButton">
<item name="android:padding">12dp</item>
</style>
Util
The ViewUtils.onGlobalLayout you'll see is just a util method for handling some ViewTreeObserver.OnGlobalLayoutListener boilerplate.
public static void onGlobalLayout(final View view, final Runnable runnable) {
final OnGlobalLayoutListener listener = new OnGlobalLayoutListener() {
@Override
public void onGlobalLayout() {
view.getViewTreeObserver().removeOnGlobalLayoutListener(this);
runnable.run();
}
};
view.getViewTreeObserver().addOnGlobalLayoutListener(listener);
}
Bringing it altogether
So, now that we've:
- Calculated the selected text bounds
- Calculated the popup bounds
- Calculated the difference and determined the popup offsets
- Provided a way to listen for scroll changes and selection changes
- Created our
Activityand popup layouts
Bringing everything together may look something like:
public class ActionModePopupActivity extends AppCompatActivity
implements ScrollChangeListener, SelectionChangeListener {
private static final int DEFAULT_WIDTH = -1;
private static final int DEFAULT_HEIGHT = -1;
private final Point currLoc = new Point();
private final Point startLoc = new Point();
private final Rect cbounds = new Rect();
private final PopupWindow popupWindow = new PopupWindow();
private final ActionMode.Callback emptyActionMode = new EmptyActionMode();
private NotifyingSelectionTextView yourTextView;
@SuppressLint("InflateParams")
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_action_mode_popup);
// Initialize the popup content, only add it to the Window once we've selected text
final LayoutInflater inflater = LayoutInflater.from(this);
popupWindow.setContentView(inflater.inflate(R.layout.view_action_mode_popup, null));
popupWindow.setWidth(WRAP_CONTENT);
popupWindow.setHeight(WRAP_CONTENT);
// Initialize to the NotifyingScrollView to observe scroll changes
final NotifyingScrollView scroll
= (NotifyingScrollView) findViewById(R.id.notifying_scroll_view);
scroll.setScrollChangeListener(this);
// Initialize the TextView to observe selection changes and provide an empty ActionMode
yourTextView = (NotifyingSelectionTextView) findViewById(R.id.notifying_text_view);
yourTextView.setText(IPSUM);
yourTextView.setSelectionChangeListener(this);
yourTextView.setCustomSelectionActionModeCallback(emptyActionMode);
}
@Override
public void onScrollChanged() {
// Anchor the popup while the user scrolls
if (popupWindow.isShowing()) {
final Point ploc = calculatePopupLocation();
popupWindow.update(ploc.x, ploc.y, DEFAULT_WIDTH, DEFAULT_HEIGHT);
}
}
@Override
public void onTextSelected() {
final View popupContent = popupWindow.getContentView();
if (popupWindow.isShowing()) {
// Calculate the updated x/y pop coordinates
final Point ploc = calculatePopupLocation();
popupWindow.update(ploc.x, ploc.y, DEFAULT_WIDTH, DEFAULT_HEIGHT);
} else {
// Add the popup to the Window and position it relative to the selected text bounds
ViewUtils.onGlobalLayout(yourTextView, () -> {
popupWindow.showAtLocation(yourTextView, TOP, 0, 0);
// Wait for the popup content to be laid out
ViewUtils.onGlobalLayout(popupContent, () -> {
final Rect cframe = new Rect();
final int[] cloc = new int[2];
popupContent.getLocationOnScreen(cloc);
popupContent.getLocalVisibleRect(cbounds);
popupContent.getWindowVisibleDisplayFrame(cframe);
final int scrollY = ((View) yourTextView.getParent()).getScrollY();
final int[] tloc = new int[2];
yourTextView.getLocationInWindow(tloc);
final int startX = cloc[0] + cbounds.centerX();
final int startY = cloc[1] + cbounds.centerY() - (tloc[1] - cframe.top) - scrollY;
startLoc.set(startX, startY);
final Point ploc = calculatePopupLocation();
popupWindow.update(ploc.x, ploc.y, DEFAULT_WIDTH, DEFAULT_HEIGHT);
});
});
}
}
@Override
public void onTextUnselected() {
popupWindow.dismiss();
}
/** Used to calculate where we should position the {@link PopupWindow} */
private Point calculatePopupLocation() {
final ScrollView parent = (ScrollView) yourTextView.getParent();
// Calculate the selection start and end offset
final int selStart = yourTextView.getSelectionStart();
final int selEnd = yourTextView.getSelectionEnd();
final int min = Math.max(0, Math.min(selStart, selEnd));
final int max = Math.max(0, Math.max(selStart, selEnd));
// Calculate the selection bounds
final RectF selBounds = new RectF();
final Path selection = new Path();
yourTextView.getLayout().getSelectionPath(min, max, selection);
selection.computeBounds(selBounds, true /* this param is ignored */);
// Retrieve the center x/y of the popup content
final int cx = startLoc.x;
final int cy = startLoc.y;
// Calculate the top and bottom offset of the popup relative to the selection bounds
final int popupHeight = cbounds.height();
final int textPadding = yourTextView.getPaddingLeft();
final int topOffset = Math.round(selBounds.top - cy);
final int btmOffset = Math.round(selBounds.bottom - (cy - popupHeight));
// Calculate the x/y coordinates for the popup relative to the selection bounds
final int scrollY = parent.getScrollY();
final int x = Math.round(selBounds.centerX() + textPadding - cx);
final int y = Math.round(selBounds.top - scrollY < cy ? btmOffset : topOffset);
currLoc.set(x, y - scrollY);
return currLoc;
}
/** An {@link ActionMode.Callback} used to remove all action items from text selection */
static final class EmptyActionMode extends SimpleActionModeCallback {
@Override
public boolean onCreateActionMode(ActionMode mode, Menu menu) {
// Return true to ensure the yourTextView is still selectable
return true;
}
@Override
public boolean onPrepareActionMode(ActionMode mode, Menu menu) {
// Remove all action items to provide an actionmode-less selection
menu.clear();
return true;
}
}
}
Results
With the action bar (link to video):
Without the action bar (link to video):
Bonus - animation
Because we know the starting location of the PopupWindow and the offset location as the selection changes, we can easily perform a linear interpolation between the two values to create a nice animation when we're moving things around.
public static float lerp(float a, float b, float v) {
return a + (b - a) * v;
}
private static final int DEFAULT_ANIM_DUR = 350;
private static final int DEFAULT_ANIM_DELAY = 500;
@Override
public void onTextSelected() {
final View popupContent = popupWindow.getContentView();
if (popupWindow.isShowing()) {
// Calculate the updated x/y pop coordinates
popupContent.getHandler().removeCallbacksAndMessages(null);
popupContent.postDelayed(() -> {
// The current x/y location of the popup
final int currx = currLoc.x;
final int curry = currLoc.y;
// Calculate the updated x/y pop coordinates
final Point ploc = calculatePopupLocation();
currLoc.set(ploc.x, ploc.y);
// Linear interpolate between the current and updated popup coordinates
final ValueAnimator anim = ValueAnimator.ofFloat(0f, 1f);
anim.addUpdateListener(animation -> {
final float v = (float) animation.getAnimatedValue();
final int x = Math.round(AnimUtils.lerp(currx, ploc.x, v));
final int y = Math.round(AnimUtils.lerp(curry, ploc.y, v));
popupWindow.update(x, y, DEFAULT_WIDTH, DEFAULT_HEIGHT);
});
anim.setDuration(DEFAULT_ANIM_DUR);
anim.start();
}, DEFAULT_ANIM_DELAY);
} else {
...
}
}
Results
With the action bar - animation (link to video)
Extra
I don't go into how to attach on click listeners to the popup actions and there are probably several ways to achieve this same effect with different calculations and implementations. But I will mention that if you wanted to retrieve the selected text and then do something with it, you'd just need to CharSequence.subSequence the min and max from the selected text.
Anyway, I hope this has been helpful! Let me know if you have any questions.
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