PyQt/QListWidget自定义Item并拖拽/README.md
2018-09-14 16:42:45 +08:00

83 lines
No EOL
2.9 KiB
Markdown
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

# QListWidget 拖拽、框选
```python
# 隐藏横向滚动条
self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
# 不能编辑
self.setEditTriggers(self.NoEditTriggers)
# 开启拖功能
self.setDragEnabled(True)
# 只能往外拖
self.setDragDropMode(self.DragOnly)
# 忽略放
self.setDefaultDropAction(Qt.IgnoreAction)
# ****重要的一句作用是可以单选多选。Ctrl、Shift多选可从空白位置框选****
# ****不能用ExtendedSelection,因为它可以在选中item后继续框选会和拖拽冲突****
self.setSelectionMode(self.ContiguousSelection)
# 设置从左到右、自动换行、依次排列
self.setFlow(self.LeftToRight)
self.setWrapping(True)
self.setResizeMode(self.Adjust)
# item的间隔
self.setSpacing(5)
# 橡皮筋(用于框选效果)
self._rubberPos = None
self._rubberBand = QRubberBand(QRubberBand.Rectangle, self)
```
## 拖动Item
```python
# 实现拖拽的时候预览效果图
# 这里演示拼接所有的item截图(也可以自己写算法实现堆叠效果)
def startDrag(self, supportedActions):
items = self.selectedItems()
drag = QDrag(self)
mimeData = self.mimeData(items)
# 由于QMimeData只能设置image、urls、str、bytes等等不方便
# 这里添加一个额外的属性直接把item放进去,后面可以根据item取出数据
mimeData.setProperty('myItems', items)
drag.setMimeData(mimeData)
pixmap = QPixmap(self.viewport().visibleRegion().boundingRect().size())
pixmap.fill(Qt.transparent)
painter = QPainter()
painter.begin(pixmap)
for item in items:
rect = self.visualRect(self.indexFromItem(item))
painter.drawPixmap(rect, self.viewport().grab(rect))
painter.end()
drag.setPixmap(pixmap)
drag.setHotSpot(self.viewport().mapFromGlobal(QCursor.pos()))
drag.exec_(supportedActions)
```
## 模拟框选
```python
def mousePressEvent(self, event):
# 列表框点击事件,用于设置框选工具的开始位置
super(DragListWidget, self).mousePressEvent(event)
if event.buttons() != Qt.LeftButton or self.itemAt(event.pos()):
return
self._rubberPos = event.pos()
self._rubberBand.setGeometry(QRect(self._rubberPos, QSize()))
self._rubberBand.show()
def mouseReleaseEvent(self, event):
# 列表框点击释放事件,用于隐藏框选工具
super(DragListWidget, self).mouseReleaseEvent(event)
self._rubberPos = None
self._rubberBand.hide()
def mouseMoveEvent(self, event):
# 列表框鼠标移动事件,用于设置框选工具的矩形范围
super(DragListWidget, self).mouseMoveEvent(event)
if self._rubberPos:
pos = event.pos()
lx, ly = self._rubberPos.x(), self._rubberPos.y()
rx, ry = pos.x(), pos.y()
size = QSize(abs(rx - lx), abs(ry - ly))
self._rubberBand.setGeometry(
QRect(QPoint(min(lx, rx), min(ly, ry)), size))
```
## 截图
![截图](ScreenShot/1.gif)