[DatePicker] Add tooltips to icon buttons

Adds tooltips to the month navigation buttons in MaterialCalendar and the header toggle button in MaterialDatePicker

PiperOrigin-RevId: 853333712

Author: Material Design Team

lib/java/com/google/android/material/datepicker/MaterialCalendar.java

@@ -28,6 +28,7 @@
 import androidx.recyclerview.widget.RecyclerView.ItemDecoration;
 import androidx.recyclerview.widget.RecyclerView.OnScrollListener;
 import androidx.recyclerview.widget.RecyclerView.State;
+import androidx.appcompat.widget.TooltipCompat;
 import android.view.ContextThemeWrapper;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -534,8 +535,10 @@ public void onInitializeAccessibilityNodeInfo(
 
     monthPrev = root.findViewById(R.id.month_navigation_previous);
     monthPrev.setTag(NAVIGATION_PREV_TAG);
+    TooltipCompat.setTooltipText(monthPrev, getString(R.string.mtrl_picker_prev_month_tooltip));
     monthNext = root.findViewById(R.id.month_navigation_next);
     monthNext.setTag(NAVIGATION_NEXT_TAG);
+    TooltipCompat.setTooltipText(monthNext, getString(R.string.mtrl_picker_next_month_tooltip));
 
     yearFrame = root.findViewById(R.id.mtrl_calendar_year_selector_frame);
     dayFrame = root.findViewById(R.id.mtrl_calendar_day_selector_frame);

lib/java/com/google/android/material/datepicker/MaterialDatePicker.java

@@ -35,6 +35,7 @@
 import androidx.fragment.app.DialogFragment;
 import androidx.fragment.app.Fragment;
 import androidx.appcompat.content.res.AppCompatResources;
+import androidx.appcompat.widget.TooltipCompat;
 import android.text.TextUtils;
 import android.view.LayoutInflater;
 import android.view.View;
@@ -557,6 +558,7 @@ private void initHeaderToggle(Context context) {
     // This information is not useful; we remove the delegate and use custom content descriptions.
     ViewCompat.setAccessibilityDelegate(headerToggleButton, null);
     updateToggleContentDescription(headerToggleButton);
+    updateToggleTooltip(headerToggleButton);
     headerToggleButton.setOnClickListener(
         v -> {
           // Update confirm button in case in progress selection has been reset
@@ -565,6 +567,7 @@ private void initHeaderToggle(Context context) {
           headerToggleButton.toggle();
           inputMode = (inputMode == INPUT_MODE_TEXT) ? INPUT_MODE_CALENDAR : INPUT_MODE_TEXT;
           updateToggleContentDescription(headerToggleButton);
+          updateToggleTooltip(headerToggleButton);
           startPickerFragment();
         });
   }
@@ -577,6 +580,16 @@ private void updateToggleContentDescription(@NonNull CheckableImageButton toggle
     headerToggleButton.setContentDescription(contentDescription);
   }
 
+  private void updateToggleTooltip(@NonNull CheckableImageButton toggle) {
+    String tooltipText =
+        inputMode == INPUT_MODE_TEXT
+            ? toggle
+                .getContext()
+                .getString(R.string.mtrl_picker_toggle_to_calendar_input_mode_tooltip)
+            : toggle.getContext().getString(R.string.mtrl_picker_toggle_to_text_input_mode_tooltip);
+    TooltipCompat.setTooltipText(headerToggleButton, tooltipText);
+  }
+
   private DateSelector<S> getDateSelector() {
     if (dateSelector == null) {
       dateSelector = getArguments().getParcelable(DATE_SELECTOR_KEY);

lib/java/com/google/android/material/datepicker/res/values/strings.xml

@@ -41,9 +41,13 @@
   <string name="mtrl_picker_invalid_format_example" description="Tells a user what an example valid entry looks like. [CHAR_LIMIT=18]">Example: %1$s</string>
 
   <string name="mtrl_picker_toggle_to_calendar_input_mode" description="a11y string to indicate this button changes the input mode to a calendar [CHAR_LIMIT=NONE]">Switch to calendar input mode</string>
+  <string name="mtrl_picker_toggle_to_calendar_input_mode_tooltip" description="Tooltip for button to switch to calendar input mode [CHAR_LIMIT=60]">Switch to calendar</string>
   <string name="mtrl_picker_toggle_to_text_input_mode" description="a11y string to indicate this button changes the input mode to a text field [CHAR_LIMIT=NONE]">Switch to text input mode</string>
+  <string name="mtrl_picker_toggle_to_text_input_mode_tooltip" description="Tooltip for button to switch to text input mode [CHAR_LIMIT=60]">Switch to text input</string>
   <string name="mtrl_picker_a11y_prev_month" description="a11y string to indicate this button moves the calendar to the previous month [CHAR_LIMIT=NONE]">Change to previous month</string>
+  <string name="mtrl_picker_prev_month_tooltip" description="Tooltip for button to navigate to the previous month [CHAR_LIMIT=60]">Previous month</string>
   <string name="mtrl_picker_a11y_next_month" description="a11y string to indicate this button moves the calendar to the next month [CHAR_LIMIT=NONE]">Change to next month</string>
+  <string name="mtrl_picker_next_month_tooltip" description="Tooltip for button to navigate to the next month [CHAR_LIMIT=60]">Next month</string>
   <string name="mtrl_picker_toggle_to_year_selection" description="a11y string to indicate this button switches the user to choosing a year [CHAR_LIMIT=NONE]">Switch to year view</string>
   <string name="mtrl_picker_pane_title_year_view" description="a11y string to announce the title of the date picker pane when it displays a list of selectable years [CHAR_LIMIT=NONE]">Year view</string>
   <string name="mtrl_picker_toggle_to_day_selection" description="a11y string to indicate this button switches the user to choosing a day [CHAR_LIMIT=NONE]">Switch to Calendar view</string>