[TextInputLayout] Add support for minEms and maxEms

Resolves #2269

PiperOrigin-RevId: 423118234

docs/components/TextField.md

@@ -319,9 +319,9 @@ The recommended default `android:layout_width` is `245dp`.
 
 By default, text fields have a maximum width of `488dp`, and a minimum width of
 `56dp` for layouts without a label. If a label is present, the minimum width
-recommended is `88dp`. `android:minWidth` and `android:maxWidth` should be set
-on the `TextInputLayout` instead of on the `TextInputEditText` to avoid
-unintended behaviors.
+recommended is `88dp`. `android:minWidth` and `android:maxWidth` (as well as
+`android:minEms` and `android:maxEms`) should be set on the `TextInputLayout`
+instead of on the `TextInputEditText` to avoid unintended behaviors.
 
 You can override those values in a custom style that inherits from a
 `TextInputLayout` style or by making changes directly on the layout:

lib/java/com/google/android/material/textfield/TextInputLayout.java

@@ -200,6 +200,8 @@ public class TextInputLayout extends LinearLayout {
   EditText editText;
   private CharSequence originalHint;
 
+  private int minEms = NO_WIDTH;
+  private int maxEms = NO_WIDTH;
   private int minWidth = NO_WIDTH;
   private int maxWidth = NO_WIDTH;
 
@@ -507,10 +509,14 @@ public TextInputLayout(@NonNull Context context, @Nullable AttributeSet attrs, i
     hintAnimationEnabled = a.getBoolean(R.styleable.TextInputLayout_hintAnimationEnabled, true);
     expandedHintEnabled = a.getBoolean(R.styleable.TextInputLayout_expandedHintEnabled, true);
 
-    if (a.hasValue(R.styleable.TextInputLayout_android_minWidth)) {
+    if (a.hasValue(R.styleable.TextInputLayout_android_minEms)) {
+      setMinEms(a.getInt(R.styleable.TextInputLayout_android_minEms, NO_WIDTH));
+    } else if (a.hasValue(R.styleable.TextInputLayout_android_minWidth)) {
       setMinWidth(a.getDimensionPixelSize(R.styleable.TextInputLayout_android_minWidth, NO_WIDTH));
     }
-    if (a.hasValue(R.styleable.TextInputLayout_android_maxWidth)) {
+    if (a.hasValue(R.styleable.TextInputLayout_android_maxEms)) {
+      setMaxEms(a.getInt(R.styleable.TextInputLayout_android_maxEms, NO_WIDTH));
+    } else if (a.hasValue(R.styleable.TextInputLayout_android_maxWidth)) {
       setMaxWidth(a.getDimensionPixelSize(R.styleable.TextInputLayout_android_maxWidth, NO_WIDTH));
     }
 
@@ -1458,8 +1464,16 @@ private void setEditText(EditText editText) {
     }
 
     this.editText = editText;
-    setMinWidth(minWidth);
-    setMaxWidth(maxWidth);
+    if (minEms != NO_WIDTH) {
+      setMinEms(minEms);
+    } else {
+      setMinWidth(minWidth);
+    }
+    if (maxEms != NO_WIDTH) {
+      setMaxEms(maxEms);
+    } else {
+      setMaxWidth(maxWidth);
+    }
     onApplyBoxBackgroundMode();
     setTextInputAccessibilityDelegate(new AccessibilityDelegate(this));
 
@@ -1613,6 +1627,56 @@ public EditText getEditText() {
     return editText;
   }
 
+  /**
+   * Sets the minimum width in terms of ems of the text field. The layout will be at least
+   * {@code minEms} wide if its {@code layout_width} is set to {@code wrap_content}.
+   *
+   * @param minEms The minimum width in terms of ems to be set
+   * @attr ref com.google.android.material.R.styleable#TextInputLayout_android_minEms
+   * @see #getMinEms()
+   */
+  public void setMinEms(int minEms) {
+    this.minEms = minEms;
+    if (editText != null && minEms != NO_WIDTH) {
+      editText.setMinEms(minEms);
+    }
+  }
+
+  /**
+   * Returns the text field's minimum width in terms of ems, or -1 if no minimum width is set.
+   *
+   * @attr ref com.google.android.material.R.styleable#TextInputLayout_android_minEms
+   * @see #setMinEms(int)
+   */
+  public int getMinEms() {
+    return minEms;
+  }
+
+  /**
+   * Sets the maximum width in terms of ems of the text field. The layout will be at most
+   * {@code maxEms} wide if its {@code layout_width} is set to {@code wrap_content}.
+   *
+   * @param maxEms The maximum width in terms of ems to be set
+   * @attr ref com.google.android.material.R.styleable#TextInputLayout_android_maxEms
+   * @see #getMaxEms()
+   */
+  public void setMaxEms(int maxEms) {
+    this.maxEms = maxEms;
+    if (editText != null && maxEms != NO_WIDTH) {
+      editText.setMaxEms(maxEms);
+    }
+  }
+
+  /**
+   * Returns the text field's maximum width in terms of ems, or -1 if no maximum width is set.
+   *
+   * @attr ref com.google.android.material.R.styleable#TextInputLayout_android_maxEms
+   * @see #setMaxEms(int)
+   */
+  public int getMaxEms() {
+    return maxEms;
+  }
+
   /**
    * Sets the minimum width of the text field. The layout will be at least this dimension wide if
    * its {@code layout_width} is set to {@code wrap_content}.
@@ -1688,7 +1752,7 @@ public void setMaxWidthResource(@DimenRes int maxWidthId) {
    *
    * @attr ref com.google.android.material.R.styleable#TextInputLayout_android_maxWidth
    * @see #setMaxWidth(int)
-   * @see #setMaxWidthResource(int) (int)
+   * @see #setMaxWidthResource(int)
    */
   @Px
   public int getMaxWidth() {

lib/java/com/google/android/material/textfield/res/values/attrs.xml

@@ -45,11 +45,17 @@
     <!-- The text color for the hint when the text field is not activated (such
          as for the resting and disabled states). -->
     <attr name="android:textColorHint"/>
-    <!-- Makes the text field be at least this dimension wide if its width is
+    <!-- Makes the text field be at least this many ems wide if its width is
+         set to wrap_content. -->
+    <attr name="android:minEms"/>
+    <!-- Makes the text field be at most this many ems wide if its width is set
+         to wrap_content. -->
+    <attr name="android:maxEms"/>
+    <!-- Makes the text field be at least this dimension wide in pixels if its width is
          set to wrap_content. -->
     <attr name="android:minWidth"/>
-    <!-- Makes the text field be at most this dimension wide if its width is set
-         to wrap_content.  -->
+    <!-- Makes the text field be at most this dimension wide in pixels if its width is set
+         to wrap_content. -->
     <attr name="android:maxWidth"/>
 
     <!-- Whether the layout's floating label functionality is enabled. -->
@@ -238,7 +244,7 @@
     <attr name="boxStrokeErrorColor" format="color"/>
     <!-- The color to use for the box's background color when in filled box mode.
          If a non-stateful color resource is specified, default colors will be used for the hover
-         and disabled states.  -->
+         and disabled states. -->
     <attr name="boxBackgroundColor" format="color"/>
     <!-- The value to use for the box's stroke when in outline box mode, or for the underline stroke
          in filled mode. -->