> Create a regression test for > [JDK-4231298](https://bugs.openjdk.java.net/browse/JDK-4231298) > Issue: > When a JComboBox first drops down, the renderer is called for > every element in the list, even those elements that will not > actually be drawn on the screen. > > Fix: > Introduced new API to JComboBox: get/setPrototypeDisplayValue(). This API > allows the UI to calculate the display size using this prototype value rather > than iterated over a large list of items. See RFE 4289100 which also > addresses this problem. > > Testing: > 1. Tested in Mach5, 10 times per platform(macos,linux and windows) and got > all pass. > > 2. Tested in JDK 1.3.0 and JDK 1.4.0 and the results are given below. > Java 1.3.0 -> Test Failed. > $ jdk1.3/bin/java JComboBoxPrototypeTest > getListCellRendererComponent index = -1, isSelected = false, cellHasFocus = > false > Value of the Counter is 1 > .... > getListCellRendererComponent index = -1, isSelected = false, cellHasFocus = > false > Value of the Counter is 101 > Test Failed > java.lang.RuntimeException: Custom Renderer got called 101 times, expected is > maximum 6 times > at JComboBoxPrototypeTestOld.main(JComboBoxPrototypeTest.java:107) > > Java 1.4.0(added a call to setPrototypeDisplayValue()) -> Test Passed. > $ j2sdk1.4.0/bin/java JComboBoxPrototypeTest > getListCellRendererComponent index = -1, isSelected = false, cellHasFocus = > false > Value of the Counter is 1 > getListCellRendererComponent index = -1, isSelected = false, cellHasFocus = > false > Value of the Counter is 2 > getListCellRendererComponent index = -1, isSelected = false, cellHasFocus = > false > Value of the Counter is 3 > Test Passed
Manukumar V S has updated the pull request incrementally with one additional commit since the last revision: Removed unwanted comment text ------------- Changes: - all: https://git.openjdk.java.net/jdk/pull/7905/files - new: https://git.openjdk.java.net/jdk/pull/7905/files/2d5c9fb8..ce0e62e9 Webrevs: - full: https://webrevs.openjdk.java.net/?repo=jdk&pr=7905&range=01 - incr: https://webrevs.openjdk.java.net/?repo=jdk&pr=7905&range=00-01 Stats: 17 lines in 1 file changed: 0 ins; 17 del; 0 mod Patch: https://git.openjdk.java.net/jdk/pull/7905.diff Fetch: git fetch https://git.openjdk.java.net/jdk pull/7905/head:pull/7905 PR: https://git.openjdk.java.net/jdk/pull/7905
