The Importance of Measure
summary
Explains how Android runs a top‑down measure then layout then draw, why onMeasure must call setMeasuredDimension, and how MeasureSpec modes (UNSPECIFIED, EXACTLY, AT_MOST) and resolveSize determine final size. Shows a custom 500×500 dp view that still gets clipped inside a 200×200 parent, notes measurement can be invoked four times in tricky cases and must finish within 16 ms, and gives concrete fixes for padding, text sizing, and a ViewPager height workaround (measure children with UNSPECIFIED and use the max).
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chapters (13)
- 0:00Introduction to measurement
- 1:10Android layout phases
- 2:36Parent-child measurement process
- 5:05Understanding measure specs
- 6:32Breaking measure rules demo
- 8:38Measure spec quiz examples
- 14:57Using MeasureSpec class
- 17:01Proper measurement techniques
- 18:23Accounting for padding
- 20:11Measuring content correctly
- 21:56ViewGroup measurement tips
- 22:18Custom ViewPager example
- 25:51Summary and resources
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