通常修改屏幕显示大小会通过调整屏幕密度来实现，但这调整的是整体的大小。客户会经常要去调整至合适大小，需要修改字体默认大小可参考本文的内容

需求：字体默认为小

根据packages/apps/Settings/src/com/android/settings/display/FontSizePreferenceController.java

public class FontSizePreferenceController extends BasePreferenceController {

public FontSizePreferenceController(Context context, String key) {

super(context, key);

}

@Override

public int getAvailabilityStatus() {

return AVAILABLE;

}

@Override

public CharSequence getSummary() {

final float currentScale = Settings.System.getFloat(mContext.getContentResolver(),

Settings.System.FONT_SCALE, 1.0f);

final Resources res = mContext.getResources();

final String[] entries = res.getStringArray(R.array.entries_font_size);

final String[] strEntryValues = res.getStringArray(R.array.entryvalues_font_size);

final int index = ToggleFontSizePreferenceFragment.fontSizeValueToIndex(currentScale,

strEntryValues);

return entries[index];

}

}

可知字体大小是由Settings.System.FONT_SCALE来控制的

根据packages\apps\Settings\src\com\android\settings\display\ToggleFontSizePreferenceFragment.java

@Override

public void onCreate(@Nullable Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

final Resources res = getContext().getResources();

final ContentResolver resolver = getContext().getContentResolver();

// Mark the appropriate item in the preferences list.

mEntries = res.getStringArray(R.array.entries_font_size);

final String[] strEntryValues = res.getStringArray(R.array.entryvalues_font_size);

final float currentScale =

Settings.System.getFloat(resolver, Settings.System.FONT_SCALE, 1.0f);

mInitialIndex = fontSizeValueToIndex(currentScale, strEntryValues);

mValues = new float[strEntryValues.length];

for (int i = 0; i < strEntryValues.length; ++i) {

mValues[i] = Float.parseFloat(strEntryValues[i]);

}

getActivity().setTitle(R.string.title_font_size);

}

可知修改的大小应满足对应值：

packages/apps/Settings/res/values/arrays.xml

Small

Default

Large

Largest

0.85

1.0

1.15

1.30

故修改如下：

--- a/alps-mp-t0/vendor/mediatek/proprietary/packages/apps/SettingsProvider/src/com/android/providers/settings/DatabaseHelper.java

+++ b/alps-mp-t0/vendor/mediatek/proprietary/packages/apps/SettingsProvider/src/com/android/providers/settings/DatabaseHelper.java

@@ -2272,6 +2272,8 @@ class DatabaseHelper extends SQLiteOpenHelper {

loadBooleanSetting(stmt, Settings.System.ACCELEROMETER_ROTATION,

R.bool.def_accelerometer_rotation);

+

+ loadSetting(stmt, Settings.System.FONT_SCALE, 0.85f);

loadIntegerSetting(stmt, Settings.System.USER_ROTATION, R.integer.def_user_rotation);

diff --git a/alps-mp-t0/vendor/mediatek/proprietary/packages/apps/SettingsProvider/src/com/android/providers/settings/SettingsHelper.java b/alps-mp-t0/vendor/mediatek/proprietary/packages/apps/SettingsProvider/src/com/android/providers/settings/SettingsHelper.java

old mode 100644

new mode 100755

index 440bb67..6fd6c72

--- a/alps-mp-t0/vendor/mediatek/proprietary/packages/apps/SettingsProvider/src/com/android/providers/settings/SettingsHelper.java

+++ b/alps-mp-t0/vendor/mediatek/proprietary/packages/apps/SettingsProvider/src/com/android/providers/settings/SettingsHelper.java

@@ -360,7 +360,7 @@ public class SettingsHelper {

mContext.getContentResolver(), name, defaultScale);

return Math.abs(currentScale - defaultScale) >= FLOAT_TOLERANCE;

case Settings.System.FONT_SCALE:

- return Settings.System.getFloat(mContext.getContentResolver(), name, 1.0f) != 1.0f;

+ return Settings.System.getFloat(mContext.getContentResolver(), name, 0.85f) != 0.85f;

default:

return false;

}