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Oleksandr Melnykov
bdb4278523
Summary:
Fabric expects the measure method to return the size in density-independent pixels, but getMeasuredWidth and getMeasuredHeight return pixels on Android, so we have to convert these values before returning to C++.
Check the method createUpdateLayoutMountItem in Binding.cpp:
```
local_ref<JMountItem::javaobject> createUpdateLayoutMountItem(
const jni::global_ref<jobject> &javaUIManager,
const ShadowViewMutation &mutation) {
...
int x = round(frame.origin.x * pointScaleFactor);
int y = round(frame.origin.y * pointScaleFactor);
int w = round(frame.size.width * pointScaleFactor);
int h = round(frame.size.height * pointScaleFactor);
auto layoutDirection = toInt(newChildShadowView.layoutMetrics.layoutDirection);
return updateLayoutInstruction(
javaUIManager, newChildShadowView.tag, x, y, w, h, layoutDirection);
}
return nullptr;
}
```
We are interested in the next two lines:
```
int w = round(frame.size.width * pointScaleFactor);
int h = round(frame.size.height * pointScaleFactor);
```
`frame.size.width` and `frame.size.height` are the values returned from the measure method in Java and they are multiplied by the screen density to get the size in pixels, which means Fabric expects these values to be DIPs.
Reviewed By: shergin
Differential Revision: D17626834
fbshipit-source-id: f9856b5d0796c75c26c84adf11e1652b22a1ddef